Help me get my CPU past 1085 mHz!

Sunny129 · Post by **Sunny129** » Thu Jan 04, 2001 8:55 pm

ok, the other night i did some CPU testing to see how far it would go. i have a P3 700E cC0 on a CUSL2 w/ a Gorb. i got it to 1085 mHz (155 fsb x 7.0) @ 1.85v. win98 wouldnt boot @ 1.7v or 1.75v, and i got win98 to boot at @ 1.8v but i got explorer errors and the blue screen of death once i was in windows. so i tried it with 1.85v and everything was stable. i then tried to go to 1092 (156 fsb x 7.0) and i got a windows protection error in DOS just b4 the desktop appeared, forcing me to restart. every attempt after that resulted in a system hang. i would go into BIOS and set the FSB to 156 mHz and exit. the system reboots and automatically loads the BIOS again telling me that my system hung the last time i tried to boot, forcing me to lower the FSB settings again. when OCing to 1092 mHz i have two options for the FSB/DRAM/PCI ratio:

1) 156:156:39 (133/133/33 ratio)
2) 156:117:39 (133/100/33 ratio)

option #1 resulted in a system hang. so i tried option #2 thinking that maybe the hang up was caused by my RAM not being able to hit 156 mHz. i still got a system hang up. so
knowing that my memory isnt the problem, and i seriously dont think that CPU temp is a problem either (seeing as how it only hits 39C full load @ 1085 mHz), maybe its the PCI bus not being able to handle 39 mHz? any suggestions as to what the problem might be would be appreciated. and also if anyone thinks i can overcome the problem and OC my CPU higher, please let me know...thanks.

PS - 1.85v is the highest Vcore i've used so far, but i'm afraid to go 1.9v or higher...

[Edited by Sunny129 on 01-04-2001 at 09:01 PM]

bitSLAP · Post by **bitSLAP** » Thu Jan 04, 2001 9:22 pm

I'm putting my money on the PCI bus. 37 mhz is about the most it'll handle. The ram @ 156 is also going to be a problem, unless you're using mushkin or vit. Using a PCI video card will help. Use only high quality PCI peripherals.

I don't know what your temperature is, but I'm guessing you can cook eggs on that golden orb...

Sunny129 · Post by **Sunny129** » Thu Jan 04, 2001 9:43 pm

actually i should have been more specific about temp. i dont run SETI@home over 1057 mHz, as 1064 mHz causes CPU temp to reach 46-48C. @ 1085 mHz, the idle CPU temp is 33-34C, and goes no higher than 39C with a full load. so actually, my temps are pretty good considering i only have air cooling. thats why i stated in my original post that i didnt think temp was a problem. and the reason i ruled out memory as a problem is the fact that it is Mushkin Pc133 rev3 (rated cas 2-2-2 @ 150 mHz, and i'm sure it can be OCed even more if cas 3 is used). so that leaves me with only the PCI bus to turn to. my PCI cards are all good quality. the highest i have OCed is 1085 mHz of course, which uses the FSB/DRAM/PCI ratio setting of 155:155:38. the next setting (which results in an OC to 1092 mHz - the one i cant hit yet) is 156:156:39, so you can see that it raises the PCI bus to 39 mHz, so maybe that is the problem. but when the PCI bus is the problem, does that mean the devices using the PCI bus are holding it back, or is it the PCI bus itself?

dadx2mj · Post by **dadx2mj** » Thu Jan 04, 2001 10:50 pm

Try pulling you PCI cards and booting with just the CPU RAM and video card. If it boots and runs then start adding your PCI cards one at a time and see which one is causing the problem. If it wont boot with out the PCI cards you may have reached the limit of the CPU. That is also a pretty high over clock for an orb to handle if I was pushing my CPU that hard I think I would get an Alpha or Global Win

Schwartz · Post by **Schwartz** » Fri Jan 05, 2001 5:00 am

I have a CUSL2 and P3-750E running at 1Ghz with 1.9v. I couldn't hit a 1Ghz with this chip until I put a mini Alpha heatsink on the CUSL2's clock generator and attached it with Arctic Silver Epoxy. You ever feel that little bastard? It will burn your finger! Now it is only slightly warm to the touch with the heatsink. I have no idea why it made the difference because the board should be able to handle way above the 133 memory bus I am running with no problem but after I stuck that on I can run run RC5 for weeks at a time.

Sunny129 · Post by **Sunny129** » Fri Jan 05, 2001 5:08 am

so your problem wasnt cooling the CPU, but rather the mobo? and where is the clock generator located on the CUSL2? maybe i should put a heatsink on it too...

EvilHorace · Post by **EvilHorace** » Sat Jan 06, 2001 12:38 am

Guess I must ask, why do you think that cpu will even OC over 1085mhz to begin with?
Have you heard of a P3 700 that'll do better than that?
If not, I'd guess that you're at its limit and a few more mhz isn't worth the potential risk nor is even likely to be noticed IMHO.
From what I've seen with cpus over 1ghz (like mine), it's really no noticeable difference if you can gain another 50-100mhz but more a mind thing in thinking that the higher #s matter.

Sunny129 · Post by **Sunny129** » Sat Jan 06, 2001 1:48 am

EvilHorace, i must agree with you that OCing a few mHz past 1085 will hardly be noticeable. i also agree that it may not be worth the risk, seeing as how i have OCed by 50% already. i guess at this point it is just curiousity that makes me want to push it further. to be honest, i have already set a limit for myself. i would like to see if i can get this CPU to 1.1 GHz, but i wouldnt attempt to go higher than that if i could reach it. i havent looked into the record books at all, and i know that there are some amazing OCing feats out there. but most of them happen with water, peltier, and even liquid nitrogen cooling. so i might as well lay the wuestion on the line right now. would a P3 700E @ 1.1 GHz be a record setter with Gorb air cooling? forgive me for asking a naive question, but i have no idea if such speeds have been reached with air cooling.

Sunny129 · Post by **Sunny129** » Sat Jan 06, 2001 2:33 am

ok, well unfortunately i hit the 1.95v barrier before i reached the 1.1GHz barrier. i know i can always try the next (and highest) Vcore setting of 2.0v, but i dont think i want to try that. call me a sissy, but that is alot of voltage for a CPU whose default Vcore is 1.7v, and it would be a shame to fry a P3 700E that already hits 1050 mHz @ 1.7v and 1092 mHz @ 1.95v. yes, thats right, i finally squeezed 1092 mHz out of her when i boosted the Vcore to 1.95v. mind you the system was rock solid at both speeds, and the only significant difference between the two was the Vcore. as if 1092 mHz isnt close enough to 1.1 GHz...i could probably callit that and get away with it when talking about estimated, rounded off speeds. of course i'll just say i couldnt quite hit 1.1 GHz just to be specific and honest. but i must say it was fun trying

. i'll probably just clock it down to about 1 GHz and run it at that speed from now on. thanks for the conversation guys, and i hope it was a wonderful story as well as a learning experience for all

...

Schwartz · Post by **Schwartz** » Sat Jan 06, 2001 4:30 am

Here it is, sorry for the delay, someone was borrowing my camera...

[Edited by Schwartz on 01-06-2001 at 04:33 AM]