It looks like the 800 MHz FSB P4's WILL be OK for overclocking

[oldfart]

Yep, cooling will be a challege too. I think that will be a problem until .09u Presott. My example was maybe extreme although people are getting pretty close to that speed already. There will also be lower clocked 800 MHz "C" chips. I forget now, but down to either 2.4 or 2.6? Same thing applies though.

Using memory that is capable of DDR 450, you are limited to a 12.5 % FSB increase without a mem ratio. No matter how you slice it, that is not what we are geting now. Use the 5:4 ratio and you get up to a 40% increase in FSB speed.

Lets try out a 2.6C example:

Overclock a P4 2.6 800 MHz FSB CPU:

Again, assume DDR450 is the memory speed limit.

DC DDR @ 1:1
13 x 225 = 2.92 GHz
DDR450

DC DDR @ 5:4
13 x 250 = 3.25 GHz
DDR400

DC DDR @ 5:4
13 x 281 = 3.63 GHz
DDR450

 

[Duvie]

Yeah...me take the last one notched up to 466ddr standards!!!! That HT would be nice as well but I think I will wait for the 1mb cache chips anyways....

 

[oldfart]

I'll likely be sitting it out as well. I had my 1.6A @ 2.4 for a year and this 2.4 @ 3.06 should keep me happy for awhile. The Prescott is a major upgrade and will be worth it. The new P4s are nice with the HT, but not a huge thing really. I may get an 875 or 865 when the prices come down to earth.

 

[oldfart]

It looks like our fearlees motherboard editor, Evan Lieb will be testing this. From his Gigabyte 8KNXP review:

With an 800MHz FSB processor your memory frequency options only increase one, and that's to include dual DDR400 support. Certainly not that impressive if you're an avid memory tweaker, but more than adequate if you're simply looking for a no frills BIOS that'll just work. However, if you're one of those users that decides to become an 800MHz FSB overclocker, you will be happy to learn that there are memory ratios above 200MHz FSB besides 1:1. In other words, you'll be able to underclock your memory for the sake of a >200MHz FSB overclock, but be aware that this isn't the most optimal scenario as you always want to match your memory's peak bandwidth with your FSB's peak bandwidth for maximum performance gains. Therefore, if you plan on purchasing an 800MHz FSB processor with FSB overclocking in mind, the main benefit will come down to just a pure core clock speed increase at the expense of less bandwidth. But, as shown by many of our past chipset and motherboard reviews, even double the bandwidth usually doesn't lead to large performance gains. In the near future we will show you exactly what type of performance you can expect from a system with an 800MHz FSB and 6.4GB/s of memory bandwidth versus an identical system with a >800MHz FSB but lower memory bandwidth.

Looking forward to it

 

[oldfart]

Overclockers.com has an article about this subject.

New Processor, New Opportunities, New Problems

Let's now take this 2.4 200MHz processor. At first, it looks like we have a big problem overclocking this puppy because there's no RAM in the world that's going to run at an FSB fast enough to get us a decent overclock from the CPU, much less faster than the CPU.

Then we find out that we can run memory slower than FSB, at a ratio of 4:5. So we take that route, and find that we can reach 270MHz FSB and a CPU of 3.24GHz, just like in the first example. Our high-end memory is running at 216MHz, slower than the 225MHz we tried before.

With fear and trepidation, we run Sandra again and to our amazement and disbelief we get a memory score rather higher than we did before.

How can this be? How can you run memory slower, and then get a higher memory score?

The answer is simple: no more bottleneck.

By increasing the FSB to 270MHz, you've done the equivalent of expanding the FSB bandwidth highway from four to six lanes. Running dual-channel memory at around 225MHz is like having five rows of cars. They don't all fit on a four-lane highway, but they do on a six-lane highway.

What's the catch? The catch is "Can you get the motherboard to run at 270MHz FSB or more easily?" Apparently, a couple extreme overclocking attempt have worked, but we don't know yet if this can consistently be done with Canterwoods, and Springdales are anybody's guess.

WizardNJ's, testing agrees with Overclockers.com

decided to play around and overclocked the fbs to 225 and set mem to 1.6x which equals 360 MHz.

Sandra 2003 mem scores with cpu @ 3.0 Ghz and mem @ 400 DDFR was 4636/4646. With CPU @ 3.375 GHz and mem @ 360 it is now 4915/4918. THis is with stock cpu heatsink cooling in Antec Lanboy case with extra front and rear fan.

The mem score is actually higher @ DDR360 with the ratio than it was @ DDR400 with no ratio.

 

[THUGSROOK]

decided to play around and overclocked the fbs to 225 and set mem to 1.6x which equals 360 MHz.

Sandra 2003 mem scores with cpu @ 3.0 Ghz and mem @ 400 DDFR was 4636/4646. With CPU @ 3.375 GHz and mem @ 360 it is now 4915/4918. THis is with stock cpu heatsink cooling in Antec Lanboy case with extra front and rear fan.

grrrrr!
screw sandra ~ i wanna see real benchmark scores! :|

3.375ghz 360dcddr? very close to my system ~ but how well does it bench? (i mean besides sandra!)

THAT is the question that needs to be answered

 

[THUGSROOK]

to clarify....

yes we all know that raising the fsb/memory gives a nice boost in scores ~ thats old news.
but what we wanna know RIGHT NOW is: does raising JUST the fsb (and not memory) still have the same effect? :Q

 

[JSSheridan]

Is there going to be a problem cooling the chipsets on the board when overclocking? They are going to have high throughput and I could see that being an issue.

Someone could run some benchmarks of their current DC-DDR system at 166FSB with 5:4 mem ratio (266DDR) and compare that to their 133FSB benchmarks. A shame that the 7205's don't have ratios. If only someone had a SIS655. Peace.

 

[oldfart]

Originally posted by: THUGSROOK
to clarify....

yes we all know that raising the fsb/memory gives a nice boost in scores ~ thats old news.
but what we wanna know RIGHT NOW is: does raising JUST the fsb (and not memory) still have the same effect? :Q

Evan will be testing this. That should help shed some light on it. In the mean time, we need someone with an 875 mobo and an 800 MHz CPU to do some testing. I have neither . WizardNJ does, but its a 3.0. Not the ideal setup but better than nothing.

 

[shoman94]

All I can offer to you guys is what I have tested to far. I'm waiting for 800mhzP4's and a good FX GPU. My CPU is not a good overclocker...150fsb is all I can get and be stable, really stable.

3DMARK2001SE--13,622
3DMARK2003----- 1,890
PCMARK2002------ 6,312cpu, 7697-mem
UT2003(v2199)----171.1flyby, 71.3bot match
SANDRA2003------3790

 

[THUGSROOK]

to clarify a little more......

my current questions:
is 3375mhz 225fsb 360dcddr faster then 3400mhz 179fsb 358dcddr?
if so, by how much?
is it worth going to a whole new platform for now? or wait for 1mb cache?

thats all i really wanna know
looking forward to Evan's results

 

[shoman94]

Originally posted by: THUGSROOK
to clarify a little more......

my current questions:
is 3375mhz 225fsb 360dcddr faster then 3400mhz 179fsb 358dcddr?
if so, by how much?
is it worth going to a whole new platform for now? or wait for 1mb cache?

thats all i really wanna know
looking forward to Evan's results

In your case I'd have to say no....You've got a gem right there.....

 

[KillaBong]

I would just wait until they make new memory... it's already up to 1ghz ddr on video cards right?

 

[THUGSROOK]

i was thinking ~ wouldnt cas options of 3-4-4-8 be a good idea for overclockers on canterwood/springdale?

 

[oldfart]

Originally posted by: THUGSROOK
to clarify a little more......

my current questions:
is 3375mhz 225fsb 360dcddr faster then 3400mhz 179fsb 358dcddr?
if so, by how much?
is it worth going to a whole new platform for now? or wait for 1mb cache?

thats all i really wanna know
looking forward to Evan's results

Dont forget, these CPUs also have HT which gives another boost. I was thinking more of the lower clocked ones like the 2.6C. Say they overclock as well as yours:

13 x 262 FSB = 3.4 GHz
DDR420 with the 5:4 ratio.

That would be a pretty fast system keeping in mind it has HT. Would it be faster than what you are running now? I'd say yes.

Is it worth upgrading to?? Depends on the individual. There are many here that upgrade mobos and CPU's constantly. I'm not one of them I've upgraded once in a year. For someone who is still on an older platform, and wants to build a new one, it may be a good way to go. The Sprindale 865PE boards will be reasonably priced, and if a 2.6C is priced where a 2.53 is now, yes it would be a very nice option.

My whole reason for starting this was there was another thread awhile back titled something like;

"800 MHz FSB CPUs the end of overclocking?"

The answer is no. You will still be able to overclock an 800 MHz CPU just fine, and get some mad FSB speeds and HT as well. The intent was not to compare this setup to a GB or SC DDR rig, or should you upgrade to it. It's just to let people know that you can overclock one of these systems if you so desire.

 

[THUGSROOK]

but id rather run 13 x 262FSB = 3.4GHz DDR524 cas 3-4-4-8
if those cas setting were available id be all over this combo

in the mean time im still keeping a close eye on these motherboards ~ Asus P4c800 @ newegg ETA = 4/21 and extreamly overpriced im sure :Q

 

[oldfart]

MSI is not my favorite make, but do a search on pricewatch for "865PE" to see what Springdale prices look like.

 

[WizardNJ]

Tell me what you want to see benchmarked. Real programs that I have or can get. Games? I have UT2003 (D3D) and Quake3 (OGL).

What real world apps can I sue to benchmark memory performance?

let me know and I'll be happy to run tests with cpu/mem at 3.0/400 and 3.60/383

Dave

 

[THUGSROOK]

Q3 would be better.

 

[oldfart]

Thanks for helping! The standard stuff I guess. Game benches, Q3, UT/UT2K3, Serious Sam, 3DMark or whatever game stuff you have or can get a demo download for. Dont use a high res to be sure you dont hit a video card limit. 10X7x32 should be fine. Some non game stuff would also be good. MPEG1/2/4 video encoding would be nice, as would MP3 audio encoding.

 

[shoman94]

UT2003; 175flyby, 76 bot

I haven't done #Dmark2001se yet with this latest overclock.

 

[Tom]

That overclockers.com article is very interesting. I'm more of an 'overclock to get the best bang for the buck' type than an 'overclock to the bleeding ege' type. So what interests me is overclocking lower end processors to speeds of the high end processors, or even a bit beyond.

With this 1.6 ratio a budget overclock system could be..

$100 Springdale board
$200 2.4 200fsb P4 overclocked to 250fsb making it 3 gig (or a 2.6 oc'd to 3.25 gig)
$100 for 1 gig pc2700 ram(2x512 sticks) overclocked to pc3200.( or maybe pc3200 oc'd to pc3500 allowing 2.6 P4 to oc to 3.5gig)

Not too bad considering cpu prices will probably drop even more, fairly quickly I would bet. (meaning the 2.4 might get to $165 or the 2.6 might get down to $200.)

 

[oldfart]

Check this crazy guy out

Cant read too much of it, but wow.
2.4C
Asus P4C800
301 MHz FSB
3.61 GHz
DDR 482 (5:4):Q


And another
2.4C
Asus P4C800
325 MHz FSB
3.9 GHz
DDR 433 (3.2)

 

[bunnyfubbles]

Originally posted by: KillaBong
I would just wait until they make new memory... it's already up to 1ghz ddr on video cards right?

video card memory has been and always will be insanely faster than system ram. The 500MHz (1GHz DDR) DDRII in the GeForce FX 5800 Ultra won't be seen in systems anytime soon, some DDR 500 would be nice for these P4s, as I agree with Thugs on this, I doub't it will be worth doing it if you do not keep the CPU and ram synced up. AMDs on dcddr nForce2 boards gain practically nothing when the CPU fsb is cranked up without the memory bandwidth to back it up, and that 800MHz (more if you OC) fsb is a pretty big and thirsty bus, you'll want to pump as much memory down that pipe as possible.

We've got new chips and chipsets to play with, now we need new ram

 

[oldfart]

I doub't it will be worth doing it if you do not keep the CPU and ram synced up

Nope. It will be very well worth it. I dont see why this is so hard to understand.

Maybe another way..

Lets call DC DDR 1:1 "100%" BW and compare mem numbers of different chipsets.

875/865/7205 DC DDR 1:1
100%

845PE 3:4
66%

845PE 4:5
62%

845PE 1:1
50%

875/865 5:4
80%

875/865 3:2
66%


We've all seen benches of DC DDR and 845PE running 4:5 ratio. Usually, there is a 3 - 6 % difference in perfomance between the two. Maybe a little more on some apps. Some have no difference at all. This is with 62% of the BW of a DC DDR board.

The 875/865 has 80% of a 1:1 DC DDR. If a drop of 38% mem BW amounts to a 3 - 6% drop in performance, how much will a drop of 20% cause? Very little. Even dropping all the way down to 3:2 still has the mem BW of an 845PE running 3:4!

What do you gain by dropping the mem ratio? Large increases in FSB and CPU speed. Unless you have some serious quality memory, you will hit a wall in short order when overclocking 800 MHz P4 "C" CPUs. Drop the mem ratio, lose a tiny bit of mem performance to gain very large increases in performnace due to higher FSB and CPU speeds.

Are the 845E and 845PE boards we have been running all this time enormously crippled compared to DC DDR? Not at all. The 875/865 running a 5:4 will have more mem BW than any of them.

EDIT: Had the numbers wrong. fixed them