OC'ing a PIII 800EB on a CUSL2

[harpomx]

Right now my 800mhzEB is clocked at 900 and is rock solid. I want more. Better. Faster. I have bios 1003F installed and everything works fine @ 900. To get to 900, I left the core voltage at 1.65, set the speed to manual, and changed to frequency to 150:150:37 (I think it's 37).
I've had it as high as 954, but then I run into some problems. First, it won't shut down properly all the time, which is a common problem with this mobo, but the fix won't work with mine (disable legacy USB, disable SB16 Emulation) As soon as I clock it back down to 900, everything's fine again.
Ive tried setting the ratio to 133:100:33, and then upping the frequency to 172, for a cpu speed of 1032, but it won't even POST, just jumps back into the BIOS. I've upped the voltage as high as 1.75, and heat is not a problem (never above 42C), but still no luck.
I have a 256MB stick of Micron PC133 Ram @ CAS3. I hear a lot of people claim their 800EB's are running over (or near) 1GHZ. What can I do to get a stable overclock above 900?

Thanks in advance.

 

[shk]

harpomx, you must have some good RAM to make your 800EB run at 900(6x150) then.. The best I can get with stable heavy gaming im stuck at is 882mhz(6x147)CAS 322 and 933mhz CAS333 w/o games, only office apps..

I think to get aweful lot of FSB cranking, im sure most of us know about the Peltier cooling setup for the Processor and mobo. Overclockers.com has it some, but I think Text is better.

Another thing, you may have to replace the AGP/PCI Northbridge chipset(Greeny heatsink thing right next to your processor) with a better heatsink and artic silver thermal grease with it so it will help allow for further FSB cranking. This one can be found in Overclockers.com, sorry I lost the URL and running out of time, hope this helps any.

 

[shk]

oops... sorry about mis-typed "text" is better.

 

[subhuman]

Most PIII's won't go much over 1000mhz. Your chip sounds like one of them, not all chips are the same.

I can only suggest you up your voltage a bit more, I use 1.85v as my personal maximum, but I've seen some people afraid to raise it at all, and they just stick with their wimpy overclock. And there's nothing wrong with that! *cough*

Also, Try hitting the 166mhz mark. Remember, you're using an older, non-performance stick of ram, but as you mention, the divisor should take care of that. I have heard some people say they had a FSB higher than 166mhz, but you should also run over to Tom's Hardware and read his 815 Motherboard round up in the Motherboard section, I think the CUSL2 was the only board which has a clock generator which was stable at 166mhz and beyond.

I believe the MSI was fine once he added more cooling, but it's been a little while since I've read that...

 

[subhuman]

Also, I would strip the computer down to just the bare essentials, video card, ram, and CPU with huge fan. With such high FSB's, some peripherals won't like the extra PCI bus Mhz.

 

[harpomx]

I wouldn't consider it "really good" RAM, it's only Micron, which some places pass off as generic. Definitely not as good as Mushkin, let alone the PC150 RAM you have, but we have different boards, that's likely the difference between what you can clock and what I can.
I don't think temps are a big problem - like I said, it runs heavy at 42C and idle at 36C. Not great, but not bad either. That said, I'm sure there's plenty of room for me to up the Core Voltage to 1.75 or even 1.85, but the few times I've tried to reach 1GHZ, upping the voltage did nothing.
Particularily in the CUSL2 bios 1003F, which do you think would give me better results (a higher top cpu speed)?

1. Incrementing the cpu clock speed (the first thing on the screen)
2. Setting the clock speed to "Manual" and changing the ratio (3rd thing on the screen - 133:133:33) as well as the frequencies (4th thing on the screen - right now it is 150:150:37)

I have pretty much left the clock speed on manual, maybe tonight I'll try to up it that way.

 

[toph99]

drop the ram's CAS latency to CAS3, it may help some. also, unless it's some great Micron(not the value stuff) you may want to get some high-speed ram(good Micron or Mushkin)

 

[harpomx]

ram is at CAS3. I'm up to 912 stable now. I don't know about the quality of my Micron RAM, but it runs fine up to 152:152:38. Anything higher than that will POST fine and boot into windows fine, but my nic won't carry a connection to my home server. Therefore, no internet, no email, no icq... Also, for anything higher than 912, windows will not shut down - just hangs on the shut down screen. Legacy USB and SB16 Emulation are disabled. PCProbe reads the cpu temp at 31-35C, during stress. I don't know what else to do. I tried raising the Core voltage, did nothing. I assumed that upping the voltage will only help if you can't even POST. Someone told me I'm lucky to get the 800EB up as high as 900, let alone 912. 700's and 733's are often clocked over a gig, why not the 800's? AARRRRRGGGHHH!!

 

[Kelv]

Yeah, have u tried to use the setting 133:100:33?
Maybe that will work? In the manual of the motherboard it actually says that if u try to overclock to like 150 or something u should use that setting.
Also, I've seen some guy here running his CUSL2 @ 177:133:33 (Or there abouts, can't exactly remember)
This way you can be sure if it's your RAM that's playing up, or something else.
Maybe this will help.. I've got a CUSL2 as well, excellent board

 

[bonkers325]

your wont get anywhere with eb chips

 

[Schwartz]

I couldn't get a GHz until I put a heatsink on the clock generator. I got a small one from 2cooltek and some arctic siver epoxy and stuck it on.

 

[harpomx]

Kelv,

I tried the 133:100:33 setting (it says right in the BIOS to use that for anything over 145fsb), and surprisingly, it did absolutely nothing. So I figured I might as well put the ratio back up to 133:133:33 even though they say not to, since it works fine. At 912, everything's fine. At 918, the NIC drops connections, windoze won't shut down. Which part of the process would be causing those two problems? FSB? RAM? PCI? I thought it might be not enough voltage, so I raised it, still nothing. Jee. Sus.

Where can you get the ratio 177:133:33? That would be shweet. My Bios only goes up to 166.

Schwartz,

A heatsink for your clock generator, eh? Interesting. Now where would I find the clock generator on the board? Also, what problems were you having before you did that? What chip/mobo combo do you have?

 

[Schwartz]

The mobo is a CUSL2 and the chip is a P3 750E. I could not hit 133 for the life of me. Then I found out how hot the clock generator was getting so I decided to get one of these:

Heatsink

and some of this:

Epoxy

and bam, 1Ghz. The chip is the one located to the top left of the dip switches. Go ahead touch it, you'll know if you found the right one.

 

[subhuman]

It's VERY POSSIBLE your NIC can't handle the higher PCI bus speeds the 166mhz FSB produces.

The only way (or, at least, most straight forward way) to verify this is to remove all cards except Video, RAM and CPU.