WIP: Karaktu's (and Zap's!) Unofficial Guide to mobile Celeron overclocking success!

[Karaktu]

Please Note: I no longer take an active role in this thread and also do not maintain it. The important links still work, but many of the incidental ones do not as many motherboards and such are out of production.


After answering the same questions over and over and over (and over!) for the last year (probably more) on the Forums, I'm finally going to take the time to write a relatively comprehensive guide on what to do with these wonder chips that get "no respect."

All contributions are welcome, but you are required to be extrememly specific when offering information so that it doesn't lead to 10 people asking, "what about..."

I am, by no means, a "final authority" on mobile Celerons (after all, Jon187 is the one who introduced me to them), but I may very well have had my hands on more than anyone else.

Intel's Northwood Mobile Celeron

Full list of Intel sSpec IDs (Note: This Guide is in reference to the 1.5Ghz and faster CPUs; the slower mobile Celerons are not based on the Northwood core.)

Picture of the Mobile Celeron processor Note the lack of a heatspreader!

These are NOT Celeron M processors!

Before Intel introduced the desktop Celeron "D" CPU (Prescott-based with SSE3), the mobile Celeron was the only 256k cache socket 478 chip with the "Celeron" name. All desktop varities were 128k cache, higher voltage and performed miserably. That is not the case with the mobile variants!

By default, these chips are designed to work on a 100MHz quad-pumped bus (400MHz) at 1.3v. Due to the wonders of the Internet and bored people worldwide, it's a no-brainer to get these working on a 133MHz FSB just by isolating a BSEL0 pin (covered below) for an instant speed boost. But even better, with the right motherboard and some extra volts, these chips perform just as well as a full-fledge Pentium 4 in most applications (especially games) that don't utilize HyperThreading (HT), often hitting 3.2 - 3.4Ghz.

My two favorite mobile Celerons

The 1.6GHz and 1.8GHz mobile Celeron CPUs are my favorites. The 1.6GHz CPU will often hit 3.2GHz at 200/800FSB and 1.65v or 2.66GHz at 166/664FSB and 1.25v while the 1.8GHz CPU will hit 3.0GHz at 166/664FSB and 1.65v or 2.4Ghz at 133/533 FSB and 1.25v. For obvious reasons, these are good numbers. I've also come to appreciate the 2.0 and 2.4GHz mobile Celerons as they hit 3.2GHz on a 160MHz FSB and 133MHz FSB, respectively.

My experience has been that the general limitations of the CPUs are 2.4 - 2.6GHz at their rated (1.3) voltage, and 3.1 - 3.5GHz at 1.6 - 1.7v. I've never run more than 1.7v through the CPUs since this is considered pushing the upper limits of "safe" with the Northwood core, but at least one crazy person water cooled a mobile Celeron, through 1.9v at it and got over 4GHz (and, of course, killed the CPU in no time).

Steppings

The most common stepping for a mobile Celeron is "C1" followed by the more rare "D1." In theory, a newer stepping like the D1 should overclock better, but in my limited experience with D1s, that hasn't been true. If you have a choice for the same price, I'd say to go with the D1.

The big question: What motherboards support the mobiile Celeron?

Official answer: NONE

I have never seen a statement from any motherboard manufacturer indicating they support mobile Celeron (or P4) CPUs. But that said, many have the microcode for these chips in their BIOSes, and EVERY P4 board I've ever tried will recognize the CPU using the "bent pin trick" (covered below), but some boards are far better choices than others.

All boards listed in preference of manufacturer and model and have been personally tested by yours truly.

- ASUS motherboards (3-year direct warranty) -

P4S800-MX
- Recognizes CPU and defaults to 1.65v/ish (bend pin for 1.25v)
- Full AGP/PCI lock
- Memory ratios and 1MHz increment overclocking
- Should be your first choice when buying a motherboard for this chip IMHO
- A top choice for mATX and HTPC
- Note: all boards out now are Revision 2.00. Don't pay more for a Revision 1.04 as it's old stock.

P4SP-MX
- SiS 651 chipset
- Works stock at 1.6v
- 1MHz FSB increments to 166MHz
- Supports DDR400
- Onboard coaxial digital out (great for HTPC!)

P4P800 or P4P800 Deluxe
- Recognizes CPU and defaults to 1.65v (bend pin for 1.25v)
- Full range of voltage selections
- Full AGP/PCI lock
- Memory ratios and 1MHz increment overclocking
- Overclocking can be limited by memory choice and has never been fully isolated to specific brand or speed, but I've never had a problem with Corsair Value Select

P4P8X (if you can find it)
- Can be flashed with a P4P800 BIOS
- Essentially the same as a P4P800, but likely the northbridge won't overclock as far

P4S800
- Recognizes CPU and defaults to 0.9v
- Full range of voltage selections
- Full AGP/PCI lock
- Memory ratios and 1MHz increment overclocking
- On some boards, system will fail to POST on soft reboot...have not figured out why

P4P800-VM
- Recognizes CPU and defaults to 1.65v
- Full AGP/PCI lock
- BSEL0 mod a must with this board so chip defaults to 133MHz and 1:1 memory ratio is an option for maximum overclocking (otherwise you're at a 4:5 ratio)
- Need to use ClockGen for overclocking
- If you need dual channel and mATX, this is your best choice
- If it was easier to overclock, it would be my #1 choice

P4S800D
- The only motherboard I have ever used that detects a mobile Celeron at 1.2v without bending the pin
- Only allows for a .5v voltage increase in the BIOS

P4G533-LA REV1.02 (Comes froms a HP Pavilion 533W starting with MX serial #)
- Recognizes CPU as a Intel Pentium 4 1.8GHz (works without bent pin)
- Defaults to an unknown voltage
- Tested with BIOS v3.10
- No overclocking options what so ever that I know of.
- Intel 845GL Northbridge
- ICH4 Southbridge

- MSI motherboards (3-year direct warranty) -

655 MAX-FISR (HT Ready), MS-6730
- Recognizes CPU and defaults to 1.58v (bend pin for 1.16v, but no adjustments available if you do so)
- Full BIOS FSB/memory ratio/voltage adjustments (1.6v - 1.85v)
- Any version of this (655 MAX) motherboard is fine, FISR has the most options
- Chipset limitation seems to be in the 150 - 160 FSB range
- My #1 choice for full-size ATX HTPC (in other words, it's what I use)

661FM-L, MS-6540G
- Pin needs to be bent
- Only FSB options are 100/133/200, so 133 is likely all you'll get due to the voltage
- Nice features and stable
- New versions of this board are available, but I haven't tested them...please report if you have!

- Gigabyte motherboards -

GA-8S661FXM
- BSEL0 pin needs to be bent
- Defaults to 1.2v, though I have one board that does 1.25v
- Full AGP/PCI locks
- 1MHz increment overclocking and memory ratios
- Very stable
- New versions of this board are available, but I haven't tested them...please report if you have!

GA-8S648FX-L
- BSEL0 pin needs to be bent
- Defaults to 1.2v
- Full AGP/PCI locks
- 1MHz increment overclocking and memory ratios
- Mild voltage adjustments in percentages up to 10% (1.37v)
- New versions of this board are available, but I haven't tested them...please report if you have!

- ECS Boards: -

661FX-M v1.0
- Defaults to 1.6v
- Onboard Serial ATA (964 SouthBridge)
- FSB adjustable in 1MHz increments, but wacky BIOS restricts it to 132MHz FSB unless you break the 133MHz pin, which would then restrict you to 166MHz
- Running memory at anything other than 1:1 causes system lockups
- AGP/PCI locks don't seem stable

PT800CE-A REV1.0A (HT Ready)
- Recognizes CPU as Mobile Intel Celeron 1.80Ghz
- Defaults to 1.55v (bend pin for 1.20v)
- Tested with BIOS v1.1A and v1.1E

- VIA VT8753 Northbridge
- VIA VT8233 Southbridge
- 1Mhz increments in the BIOS and onboard jumpers to switch in between 100-133-200MHz bus
- Can boost voltage up to 6% higher

P4VXMD REV1.0
- Recognizes CPU as Intel Celeron 1.8AGhz
- Defaults to 1.60v (bend pin for 1.20v)
- Tested with BIOS v1.2D
- VIA PT800CE Northbridge
- VIA VT8237 Southbridge
- Can switch bus speed in the BIOS in jumps
- Can boost voltage up to 6% higher

- Jetway Boards -

650DF

- No pin mods required
- SIS 651 chipset
- Onboard video, 5.1 sound and optical out
- FSB adjustments and memory ratios but no PCI locks
- Great candidate for tiny HTPC

Barebone Systems

ASUS Vintage barebones SIS 661FX system
- P4S800-MX motherboard version 2.01
- AMI instead of AWARD BIOS
- Needs pin bent
- Limited overclocking options / 133 FSB all to expect

I'm not sure why ASUS put a different BIOS on these. It should be possible to hot flash the BIOS to AWARD, but I haven't tried it.

eCube EG65
- Requires bent pin to POST, defaults to 1.2v
- No voltage adjustments
- No FSB adjustments
- Limited HSF selections due to non-removable drive cage
- Dual side windows
- Great candidate for 133FSB pin mod and stylish HTPC

Shuttle XPC Model SB65G2
- Defaults to 1.62v/ish
- Full AGP/PCI locks
- 1 MHz increment overclocking and memory ratios
- Full range of voltage selections!
- Dual channel memory
- Fan speed controlled by BIOS/temperature
- Depending on the I.C.E. heat sink, may need to use the "penny trick" or just use a low-profile HSF (like a Zalman CNPS5700 without the shroud)
- 220 watt PSU makes it hard to recommend anything more powerful than a 9600XT
- Integrated 802.11b is dated, but fine for web surfing

This rig was recommended to me by BigBadBiologist, and what a pleasant surprise it is! It's full of features in the BIOS and has crazy-high voltage selections, allowing for better overclocks. A mobile Celeron in this machien makes a superb HTPC or LAN gaming box on the cheap and cool!

Shuttle XPC Model SB61G2V3
- Requires bent pin to POST, defaults to 1.2v
- Full range of voltage options
- 250-watt PSU gets you into 9800 Pro territory

Heatsinks

Since the mobile Celeron does not have an integrated heat spreader, you need to be SURE the heat sink you choose is making contact with the core BEFORE applying power, or there's a good chance you'll have a dead CPU in a nanosecond. IMHO, the best way to verify a heatsink will work for you is to install it, then remove it and verify that the excess thermal grease was pushed aside from the pressure of the heatsink being installed. If you have any doubt, use a different heat sink.

Remember that you don't necessarily need anything fancy if you're going to be running at the lower voltages. At 1.2/1.3v and even 2.65GHz, there's no need for fan noise.

Heatsinks that I have tested and verified to work:

Thermalright SLK 900/947/948U
Zalman CNPS7000/A/B AlCU/CU
Zalman CNPS5700D-Cu (with and without shroud)
Spire CopperStream II (my personal favorite)
Spire Easystream
Any Intel socket 478 retail HSF

Heatsinks I have tested and verified need the "penny" or Zap's "floppy trick":

Vantec CCK 7025
Zalman/PCToys CNPS6500 (I'm hoping to get around to seeing how this works passively with a CPU at 1.2v)
CPUMate D132HM4

Power supply (PSU) requirements

So how much juice do you need to power your new 3GHz+ system? Not much...in fact, a fully loaded 3.2GHz 200FSB system with two opticals, a hard drive and Radeon 9600 non-Pro 256 meg will run just fine on a 240-watt PSU (consuming around 150-watts under load)...and do it silently. I do recommend that you use a PSU of reasonable quality, though.

Enough already, how do I mod this chip?

There are three basic mods that can be done to mobile Celerons.

1) The "bent pin" trick. By bending or breaking pin AE1 (indicated in WHITE), motherboards that don't recognize a mobile Celeron should POST and default the CPU's voltage to 1.2-1.25v. I've never seen it default to its rated voltage of 1.3v. If you are careful, you should be able to pen the pin and put it back 2-3 times before it breaks off completely.

2) The 133FSB trick. Pin AD6 (highlighted in red) controls the 100/133 FSB option. Your two choices here are to break the pin off, or try isolating it with nail polish. My advice would be to test and verify the CPU works at 133FSB (which shouldn't be an issue on anything under 2GHz), then break the pin off -- there's no warranty to worry about! The pin highlighted in light blue is the 200FSB pin. I don't recommend messing with this pin unless you're absolutely certain your CPU does 200FSB (likely on a 1.5GHz CPU, very possible on a 1.6GHz CPU, but probably not going to happen above that without extreme voltage).

3) Wire wrapping (or conductive thermal grease, etc.) voltage trick. If you run into a motherboard that will POST the mobile Celeron processor without using the bent pin trick, but for some reason defaults to 1.2v and doesn't have any voltage adjustments in the BIOS, you CAN use this trick. Personally, I'd just get another motherboard...but here you go:

The pins colored green, plus one in white (AE1/VID4) are, from left to right VID4, VID3, VID2, VID1, VID0

The default for 1.2v is:

VID4=0 VID3=1 VID2=0 VID1=1 VID0=1

Simply connect VID3 and VID2 to get a changed value of 1.6v, or

VID4=0 VID3=0 VID2=0 VID1=1 VID0=1

If you then connect VID1 and VID2, you now get 1.70v; connect all the VIDs and get 1.75v.

Here's what the CPU would look like with VIDs 4, 3, 2 and 1 connected with conductive ink.

Refer to the Mobile Intel Pentium 4 Datasheet for technical information.

Now, you may have noticed that the bent pin and the voltage wrap tricks share pin AE1 (VID4). I have no idea if you can use both "tricks" together or not as I have never tried it. Edit: It has been reported to me that if you bend the pin, you can NOT also mod the voltage.




More to come...



Credit to and some information lifted from:

rogue1979 for working with me on the wire wrapping formula;

VR-Zone's Northwood volt mod guide Note that the voltage chart is for DESKTOP chips;

Zap's FSB pin mod page;

 

[Zap]

I want to be first to jump in this thread. :thumbsup:

I've personally owned three mobile Celeron 1.6GHz. One was purchased directly from Karaktu, the others from another AT forum member (forgot name, old age will do that to a person) that originally got them from Karaktu. I traded away one of my chips and still have the other two. Oh yeah, quick correction "the mobile Celeron was the only 256k cache chip with the "Celeron" name" is true only if socket 478 is specified. Tualatin Celeron chips had 256k cache. Enough of that, lemme contribute to this guide:

Zap's FSB pin mod page

I may or may not have been the first person to actually try the FSB pin mod on a mobile Celeron. Worked great for setting the FSB detected by the motherboard to 133 or 200 (only speeds available besides default). On some board this allowed for much higher overclocks and opened up more memory multipliers.

Some heatsinks will NOT work on the mobile Celeron

The reason is that the mobile chip does not have the heat spreader, making heatsinks sit lower. The problem is that some heatsinks will touch the corners of the P4 retension bracket. Most "retail box" heatsinks will work. If you look at the bottom of them, you'll see that it is of a stepped design. Also, "flower" style retail box heatsinks seem to work okay. I've also gotten an Alpha PAL8942T heatsink working by not putting the washers on the top side of the motherboard. An alternative is to make a spacer of a few millimeters thick and use it between the core and the heatsink.

Motherboards that I've personally tried an unmodified mobile Celeron on

...forgive any inaccuracies because some of these were tried almost a year ago and I'm pulling this from memory (always a bad sign). IIRC I used newest BIOS available at the time on all these boards. Again, this was an unmodified chip.

Asus P4P800 Deluxe
- 865PE chipset
- Seemed to work okay, but never overclocked very high and also had a FSB "hole" from around 160MHz to 199MHz where the system wouldn't POST. Detected voltage was around .9 and didn't seem to increase properly, as in when I raised it the motherboard monitor would see voltage rise pretty fast, then drop back down after a certain setting. Now happily running a Deleron 320 at 3.6GHz.

Asus P4P8X-SE
- 865P chipset
- Seemed to work okay, but acted really glitchy at times. IIRC it would sometimes work fine with an overclock then suddenly wouldn't. Now happily running a desktop P4 Northwood.

Asus P4S800
- SiS 648DX chipset
- Mine will always POST initially, then if it is powered off will not POST a second time until the power is physically cut (pull the plug or flip switch on power supply) for a few seconds. Asus website used to say AGP/PCI lock, but no longer says that. I'm 99% certain it does not have such a lock, thus not being the best overclocking board unless you can run it near normally available FSB speeds of 100/133/200. Board may have died after I swapped the CPU for another one, now won't POST (haven't had time to troubleshoot yet).

Asus P4C800-E Deluxe
- 875P chipset
- I recall POSTing the mobile chip in there, then putting in my first Prescott chip. The board worked with the Prescott (2.4A) for a few minutes with a minor overclock and then died.

Abit IS7
- 865PE chipset
- Would not POST with the unmodified mobile chip. Recently sold the board.

MSI 865PE Platinum (whatever model number, the black PCB and not the red ones)
- 865PE chipset
- Would not POST with the unmodified mobile chip. After tring to overclock a Deleron in this board, board died. Second board I owned that died from overclocking a Prescott core.

MSI PT880LSR
- VIA PT880 chipset
- Would not POST with the unmodified mobile chip. Still working great after a year with a P4 2.53 (pulled from a Dell Dimension) overclocked to 3.33GHz.

MSI 645E Max
- SiS 645DX chipset
- Works great with the mobile Celeron. Will POST at over 180MHz FSB, unfortunately chipset only "officially" supports 133MHz FSB and does not have AGP/PCI lock. Board is slated to go in my HTPC (to replace the P4S800). Detects voltage at 1.60.

Albatron PX845PEV Pro
- 845PE chipset
- Would only POST at 125MHz FSB... until I did the FSB pin mod to 133, then it would POST up to 207MHz FSB!!! That's on the 845PE chipset that is rated for only 133MHz FSB. So far reasonably stable at 188MHz FSB. Motherboard has network and USB glitches, probably due to a bulging soon-to-explode capacitor near Southbridge. Currently in use with one of my mobile Celerons overclocked to 3.01GHz. Detects voltage at around 1.625v.

That's it for now. I'll edit this post in case of changes.

 

[Zap]

Karaktu, are you certain that the P4S800 and the P4S800 MX have AGP/PCI locks? Hmmm, the Asus page now says (under special OC features) "Fixed AGP/PCI frequencies." I seem to recall mine having problems between 100 and 133MHz FSB. If my board can be resurrected, I'll try it again.

 

[Karaktu]

Originally posted by: Zap
Karaktu, are you certain that the P4S800 and the P4S800 MX have AGP/PCI locks? Hmmm, the Asus page now says (under special OC features) "Fixed AGP/PCI frequencies." I seem to recall mine having problems between 100 and 133MHz FSB. If my board can be resurrected, I'll try it again.

Yup. I've sold two systems running on them at 3Ghz (188 FSB) and 3.2GHz (200FSB), and know of a handful of other peeps who have used them successfully. However, there are clearly differences in the boards, even though you can't look at them and see what it might be, that can cause problems. I've RMA'd a few to ASUS and the returned boards did not have the reboot/POSTing problem.

Edit: The P4S800-MX is currently THE board for mobile Celerons, IMHO.

 

[rogue1979]

Originally posted by: Zap
Karaktu, are you certain that the P4S800 and the P4S800 MX have AGP/PCI locks? Hmmm, the Asus page now says (under special OC features) "Fixed AGP/PCI frequencies." I seem to recall mine having problems between 100 and 133MHz FSB. If my board can be resurrected, I'll try it again.

I can vouch for the P4S800-MX, full agp/pci lock.

 

[rogue1979]

Here is some info on P4-M cpu's also. The are easily found on E-bay for $40-$65. Because all P4-M have Speedstep, they default to a 12X multiplier on a desktop motherboard, unlike the mobile Celerons that retain the stock multiplier.

Because of this and the B0 stepping found on most of the 1.2-1.6GHz P4-M's, put them on a P4S800-MX at a 200MHz fsb and you have a 2.4C with the full 512k L2 cache. They don't go much faster than that, though there are a few higher speed P4-M's that have C1 stepping and could probably overclock much higher on a motherboard that supports a 250MHz+ fsb speed.

I bought two 1.6GHz mobile Celerons from Karaktu for less than $50 and they were a great deal. Both were BO stepping and did 2133MHz at the stock 1.2v in a laptop, and about 2700MHz on the P4S800-MX that defaulted to 1.60v.

I have two 1.8GHz mobile Celerons on the way that are C1 stepping, gonna put them both on P4S800-MX boards. I will post again with the results.

I also have a 1.8GHz C1 desktop P4 that does 3GHz at default voltage and a 2.26B that hits 3.2GHz. I have done some benchmarking in 3DMark and gaming, comparing the mobile Celeron, P4-M, and desktop P4.

I found that if the fsb and memory speeds are equal, the P4-M and desktop P4 perform equally, both have 512k L2 cache.

The mobile Celeron is about 10% behind for gaming. They also seem to run a few degrees cooler. So the 1.8GHz mobile Celeron with C1 stepping at an average of 3.1GHz is about as fast 2.8GHz P4.

But at a price of just over $50, coupled with the P4S800-MX for less than $50, you have one of the best bang for the buck set ups that you can buy.

Right now this is cheaper than an AMD thoroughbred core at the average overclock of 2.1-2.2GHz and slightly faster.

Still cheaper than the mobile Barton set up and about as fast.

The cores of the P4-M and mobile Celeron don't have a heat spreader.
Simply take a 1962 or older penny (pure copper) and use as a shim. I found that using a smooth sidewalk you can use your foot to wear down the indentions on both sides in about 5 minutes. Then use sandpaper to smooth and you have a perfect spacer for about 15 minutes of work.

 

[VirtualLarry]

Originally posted by: rogue1979
The cores of the P4-M and mobile Celeron don't have a heat spreader.
Simply take a 1962 or older penny (pure copper) and use as a shim. I found that using a smooth sidewalk you can use your foot to wear down the indentions on both sides in about 5 minutes. Then use sandpaper to smooth and you have a perfect spacer for about 15 minutes of work.

LOL, that's pretty clever. I knew I read something about someone using a penny as a replacement for the heatspreader. Wasn't sure how to go about sanding down the face of one though. Thanks for the idea.

I recently started a build using a mobile P4 (S478, SL6FK, Northwood, 2.0Ghz, 1.3v), on a QDI QDI P2PE/800 Pro mobo, which is an 845PE chipset board that supports 800Mhz FSB with some overclocking options. Plus, it was only $30. I wasn't certain which desktop boards/chipsets would support mobile P4s, but I read some reviews where this was done on an Asus 845PE board, so I figured I should stay safe and stick with a known-working chipset for this experiment. I also picked up this HSF, because it looked solid, and was only $4.

Thus far, I was able to get the CPU to boot in that mobo, and it defaults to 1.65v and a 12x multi, at 400 FSB. That's good. The HSF, however, is completely flat on the bottom, and doesn't have the indentations along both sides like the retail Intel HSF does, so it actually hits the plastic heatsink retainer clips on the mobo, and doesn't make contact with the CPU at all, due to the missing heatspreader. So my temps in BIOS went up to about 83C before it shut itself off. Eh, not a good sign.

So as soon as I can find a better heatsink (found a retail Intel one, but they wanted $15 for it, no thanks), I'll see what this rig can do. I'm hoping for a fairly benign overclock of 12x and 800FSB, using PC3200 valueram, resulting in a 2.4Ghz Northy P4 sans HT. No dual-channel on this chipset, but the latency is supposed to be pretty low instead, so that's not bad. Considering someone gave me the P4 CPU, my out-of-pocket expenses (excluding the RAM I borrowed from an existing system), will run me under $40, and should be marginally faster than my existing AMD XP2000+ rig with PC2700 RAM. If I can manage to bring the voltage back down to around 1.4v, it should be rather cool-running as well.

Also been toying with the idea of getting a Celeron-D 320 chip, and OC'ing it to 3.6+Ghz, on a cheap 865PE dual-channel board, just for fun. Would cost me another $120, but that might actually offer a bit more of a performance-competitive platform for gaming, although still short of an AMD64 rig. I don't want to go all-out on a PCI-E rig just yet though.

Edit: The reason that I posted that, was to point out that the mobo I used supports mobile P4s and 800FSB, and that HSF does not work with mobiles. FYI.

 

[Zap]

Originally posted by: VirtualLarry
The HSF, however, is completely flat on the bottom, and doesn't have the indentations along both sides like the retail Intel HSF does, so it actually hits the plastic heatsink retainer clips on the mobo, and doesn't make contact with the CPU at all, due to the missing heatspreader.

Also been toying with the idea of getting a Celeron-D 320 chip, and OC'ing it to 3.6+Ghz, on a cheap 865PE dual-channel board, just for fun. Would cost me another $120, but that might actually offer a bit more of a performance-competitive platform for gaming, although still short of an AMD64 rig.

That's what I was talking about with the HSF. Perhaps you should just try to make some kind of spacer. $15 for a retail HSF is kinda high. Newegg used to have them on refurb for $5.

For better performance without breaking the bank...

I had a Deleron 320@3.6GHz. From all my reading, they are close but not guaranteed at 3.6GHz. If your chip isn't stable at that, most likely you will be stuck at around 3GHz because many boards have a FSB "hole." For instance, had the Deleron on an Asus P4P800 Deluxe. It would work great at 200MHz FSB setting in BIOS, but won't POST at all at 199MHz FSB. A more "sure thing" would be to get a Deleron 315. Only a few bucks savings, but these would be more "guaranteed" at 3.4GHz overclock.

Another alternative would be to get a mobile Celeron. At 90% of the performance of a similar clocked P4 and a board that is known to hit 200MHz FSB and will POST with the low voltage mobile chips, a lucky mobile Celeron 1.6 can hit 3.2GHz at 200MHz FSB. Mine will POST at that speed just fine, but blue screen on Windows. This would be a cheap way to get near 3GHz P4 performance.

Yet another alternative would be to bite the bullet and go socket 754. Sell off your setup and get a $65 Epox Nforce3 motherboard. Then, get a $90 Sempron 2800+ (1.6GHz, 256k cache) and overclock it to well over 2GHz or get a $115 AX stepping A64 2800+ (1.8GHz, 512k cache) and overclock it to well over 2GHz. Either one should have very competitive performance.

Dear

Your Newegg.com sales order has been successfully charged to your credit/debit card
and order verification is now complete.

Sales order number:
Customer number:
Amount: $181.49
Time of charge: 2/23/2005 2:21:32 PM

I bit the bullet and ordered the A64 and Epox board today.

 

[Karaktu]

Hey Chuck, there is no B0 stepping 1.6GHz mobile Celeron, they're all C1.

If you do use the heatspreader "trick", make sure you put thermal grease on BOTH sides of it! I haven't found the need for adding a heat spreader yet, though.

When "we" first started playing with mobile Celerons, 3 - 3.2GHz was pretty top end and expensive. There's no doubt the market has changed, but for silent, upper-middle range computing or HTPC applications, I don't think you can pick a better price/peformance processor today.

 

[rogue1979]

You're right, I just checked out the Intel Processor Specs for the mobile Celeron.

1.5GHz could be the BO stepping, but 1.6GHz is only C1. I incorrectly assumed BO cuz both of mine topped out short of 3GHz at 2.7GHz.

 

[rogue1979]

Hey Zap, I'm waiting for the new socket 754 Semprons. They are set up for a 333MHz fsb instead of 400MHz, so the multiplier will be higher and I think they will have SSE3 optimizations. Should be easy to get 2.4-2.6GHz out of them, .09 micron cores with 256MB L2 cache on some. No 64-bit, but with the memory controller and half the cache gaming benchmarks will be awesome at those speeds.

I hear they are gonna cost around $70-$88!

 

[Karaktu]

Unlike mobile Celerons vs. P4s at the same clock speed, I noticed a huge performance difference between a Sempron and A64 at the same clock speed.

 

[BATCH71]

One thing to say about the "penny trick'

"BRILLIANT!!" and only costs 1 cent

 

[rogue1979]

Originally posted by: Karaktu
Unlike mobile Celerons vs. P4s at the same clock speed, I noticed a huge performance difference between a Sempron and A64 at the same clock speed.

Joe, is that between the socket A Sempron and the A64? Or is that the current 3100+ socket 754 version vs the true A64?

From what I understand the biggest boost in gaming performance comes from the on die memory controller which the socket A Semprons don't have of course.

 

[Karaktu]

Originally posted by: rogue1979

Originally posted by: Karaktu
Unlike mobile Celerons vs. P4s at the same clock speed, I noticed a huge performance difference between a Sempron and A64 at the same clock speed.

Joe, is that between the socket A Sempron and the A64? Or is that the current 3100+ socket 754 version vs the true A64?

From what I understand the biggest boost in gaming performance comes from the on die memory controller which the socket A Semprons don't have of course.

I had a socket 754 Sempron 3100+ at 2.475GHz and clocked a 3200+ 1 meg L2 cache DTR A64 at 2.475GHz (same HTT/multiplier settings), and the A64 was 15-20% faster in just about everything I tested.

One other thing I've noticed about the A64 chips I've had...they're as stable under the 64-bit version of XP as the "standard" version when overclocked.

I just wouldn't "waste" my money on a Sempron CPU when an A64 isn't much more unless all I wanted to do was a relatively inexpensive gaming box. But then, if I was going to do that....what's the main topic of this thread again?

 

[Zap]

I had a socket 754 Sempron 3100+ at 2.475GHz and clocked a 3200+ 1 meg L2 cache DTR A64 at 2.475GHz (same HTT/multiplier settings), and the A64 was 15-20% faster in just about everything I tested.

I don't think that's too valid a comparison since most lower end A64 chips these days are Newcastles with 512k cache.

That said, I'm pleased with my mobile Celerons and I'm sure I'll be pleased with my AX core A64 when it shows up. Next on my agenda... try replacing the bulging capacitor on the Albatron and if that doesn't fix the glitches, get one of those Asus P4S800-MX boards if I can find a deal. I'm also pretty pleased with my mobile Bartons. Only chips I haven't been too happy with in the past year or so are P4 chips. :Q Let's see, one 2.4A Preshott would OC to 3+GHz but hit over 80ºC. The other one won't POST in my Asus P4S800 board (after I removed a working mobile Celeron from it). A 2.6C is glitchy even at default speeds, though seems okay if HyperThreading is turned off in BIOS. I also bought a 3.0E from Fry's with a disposable ECS motherboard. The motherboard was fine. CPU was DOA. Just not getting any joy from P4 CPUs.

 

[rogue1979]

Update:

Two 1.8GHz mobile Celerons both on P4S800-MX motherboards.

One is at 2952MHz and the other at 2974MHz. This is at the default of 1.61v.
(Prime95, gaming and multi-tasked stable)

These are both in micro-atx cases with good cooling. Both are set up with 5 and 7-volt fan mods and are extremely quiet. I could easily use the wire hoop trick to get 1.65v and push both cpu's over 3.0GHz. But in my experiences a small boost in core voltage equals substatially more heat with Northwood cores at higher speeds, not worth the extra 100MHz or so.

According to Sandra the benchmarks put the mobile Celeron almost dead even with a 3.0GHz P4 in Multimedia and Arithmetic. The Asus P4S800-MX has awesome memory dividers, so at 163 and 165MHz fsb speeds memory is running asynch at more than 400MHz DDR.

3DMark is about 4% ahead of a P4 2.4C (800MHz fsb), so this is probably 10-12% behind a P4 3.0GHz with the full 512k L2 cache. I was too lazy to bench any specific games, but usually they follow closely to 3DMark results.

Overall I am pleased with the performance of these $50 processors.

They also make awesome replacements for laptops with desktop P4 processors which run notoriusly hot and often throttle back. Break off the right pin and they will default to a 133MHz fsb and 2.4GHz @1.3v, running much cooler than a desktop Northwood at 1.5-1.575v.

 

[Karaktu]

Chuck, what BIOS rev are you using? 1010? What does CPU-Z report the voltage as? It says 1.696 in mine.

 

[rogue1979]

I am currently using bios 1010. One board reads 1.62v and the other 1.60v.
Sandra Lite 2005 reports the voltages at 1.65v and 1.63v respectively.

I already know that the wire hoop trick will give me about .03 volts more and easily get both cpu's over 3.0GHz.

But they are both running very cool, quiet and plenty fast. Like I mentioned both rigs are set up for silent running, the last 100MHz or so isn't worth the extra heat for me. Both cpu's are running about 48C under Prime95, idling at about 32C.

 

[jbmx4life]

I have a socket478 non-mobile Celeron 2.0 and I an wonderin if the vcore mod will work for it. I have tried to put it to 133fsb but it won't stay stable and my board doesn't allow for the vcore to be changed. I got a good cooler on it and would like to bump the vcore up a bit to be able to run at the 133fsb. I would go to a higher FSB but myboard doesn't support that either, lol.

 

[Zap]

You may have to mod vcore as weill as FSB. My Albatron board would not run my mobile at over around 125MHz FSB until I did a FSB mod to it, now it runs at 188MHz FSB with no other mods. Unfortunately this is risky. I've done this mod before to a desktop Celeron 2.0 that was already known to be good at 2.66GHz (actually, it ran fine at 2.9GHz), but on an unknown chip...

I'm working on a better picture for Karaktu that shows which pins are what for voltage and FSB... Stay tuned.

 

[jbmx4life]

well my board will not go over the 133fsb under any circumstances so I don't think that the fsb mod is necessary. If you want to you can go and check out some specs and stuffs about my board. ECS P4S5A/DX+ <---- that is the mobo that I got and the fastest processor it can handle is a P4 3.06 (533FSB). There is not adjustment for the vcore in the BIOS that is why I was figuring this vcore mod to work just to get it up a bit. The mem might also be holding me back cuz it is only PC2100 but I cannot verify that for sure until I can get the system stable and then run memtest. This is only a back-up rig that my kids use so don't laugh (too hard...) lol. Thanks for the help

 

[Zap]

Ahh, an ECS board. Yes, you can do voltage mods. Pretty easy with thin wires.

 

[MercenaryForHire]

Owner of three Celeron-K's

- M4H

 

[Leper Messiah]

Originally posted by: rogue1979

The cores of the P4-M and mobile Celeron don't have a heat spreader.
Simply take a 1962 or older penny (pure copper) and use as a shim. I found that using a smooth sidewalk you can use your foot to wear down the indentions on both sides in about 5 minutes. Then use sandpaper to smooth and you have a perfect spacer for about 15 minutes of work.

sorry to go OT, but do you think this will work for an IHS-less A64, and decrease temps any?