Some questions about my 2.8C O/C.

[jeffro]

Here are the specs on my new rig....
P4 2.8E
512 Dual Channel Corsair XMS
P4P800

NOTE: I'm not really into screwing around too terribly much, but trying to get most outta the Rig as I can with ease and stock components.

Got it all put together and running great. Ran some bench's last nite and I'm satisfied with the 2.8 over my previous 1.8 Northwood.

So, I decided to start my OC'ing before I got too far down the road of restoring all my backups.

I went for Asus' 20% Auto Overclock which took my up to 3.36GHz. No problems with POST and no problems for the first hour of SANDRA's burn-in. Then I fell asleep. During that first hour, Asus probe showed my CPU around 43 deg. C. I was happy to see that!

Woke up this morning and the machine had rebooted at some point and got the windows "recovered from serious error" message.

So, naturally, I backed off a little bit and took it down to 3.2 GHz (229 FSB). Burn in is running at home now.

Some questions for you all:
-Is ASUS probe reliable?
-Should I be messing with AGP/PCI ratio's?
-Should I be messing with memory ratio's with my memory?
-Could my crash last night have been caused by heating? How about VCore?
-If I'm doing a "manual" OC as opposed to ASUS's auto overclock, is there anything I should adjust besides FSB if I'm just looking to go up to 229 FSB?
-Sandra vs. Prime95 burn-in? Note that Prime95 didn't seem to want to take CPU usage up to 100% since it only seemed to be using 1 thread of my hyperthreaded CPU. Also read somewhere that Sandra is good for memory checks.

For reference, I'm using Stock HSF, Thermaltake 500W PSU, Clear Lucite Case (is pretty open so I think I'm getting good airflow), Ti4400 GPU.

Edit - I know this is a log of questions to toss out at 1 time..sorry but thanks in advance!
Thanks!

[Vio1]

Asus probe is not reliable because the asus board isnt totally accurate. AS to the agp/pci ratio: leave it at 66/33 (never more). As to timings, set them to what Corsair says they work at on there website. The crash last night might very well be the v-core.... i wouldnt use auto overclock. Raise the fsb to whatever you like (prob 230-260) and run memtest86 (i think this program will tell you if your system is downright unstable pretty quickly. If you get errors or it freezes, then try raising the agp voltage a bit, and try raising your cpu voltage (no higher the 1.65v... perferably not higher then 1.625v). keep running memtest and if it runs 2 passes without error start windows and run prime95... I dont trust prime 95 much but others here do... my computer is at 257fsb (3.6ghz) and I pass memtest (more then 30 passes) and when i run prime95 it freezes my pc after 5 mins.... however I havent yet had my computer restart (and its been weeks... I have seti running 24/7, and Ive played ut04, ran all different benchmarks and havent had a prob. If youre looking to get the highest overclock possible then youre gonna have to disable HT. It usually makes an overclocked pc unstable. If youre not out to push your pc to the extreme then your cooling should be fine.

[jeffro]

Thanks for the advice. Thats the advice I was looking for!

What are comfortable CPU temps? I've heard a lot of different numbers but some opinions here would be great. 50 Deg. max? Higher than that??

[Vio1]

i have better air cooling then you do and i have: 35C idle and 47C load (however I believe my temps are this high because of the board Im using now... i had a p4p800 dlx before and I was getting idle temps of 27C and load temps of 40C.... my temps now are prob more accurate. If your over 55C then I would reduce the speed... better to have it under 50C.... since your using the p4p800 id say have a load temp no higher then 45C (cause it is most likely an actual temp of 50+C)

[jeffro]

Thanks for that perspective too. Those temps are pretty well right on what I'm getting. Around 25-27 at idle and around 43 or so at load. Hopefully the burn in is still running when I get home and I'll get a good feel for what temps I max out at with my 229MHz FSB OC at the moment.

[hUMANbEATbOX]

prime95 will show the true colours of an unstable system.

you can run memtest all month, but that stresses primarily your ram.

if prime crashes, you are not 100% stable, no matter how much gaming/seti you can do on the machine.

also, running 2 instances of prime to acheive 100% cpu usage is not required IMO. 1 p95 will do fine to test for stability, its just that winXP sees the other "cpu" as being free from tasks, so it incorrectly displays your cpu as being at only 50% load. in actual fact, the other "cpu" probably only accounts for maybe 1% of the total processing power of your chip.

[gamefoo21]

Memtest is a general system stability tester. I read it on the website it will pick out any components that are linked to reading and writing to the ram that are unstable. It can't say what the error is but it does lay a good thumpin on the Cpu, NB, and Ram. Prime is basically the same thing except its a windows app and it is susceptible to outside influences. I had it crash on me or lock the machine because it conflicted with something I had installed. I reinstall reset the clock speeds to where they were b4 and it primed for 10 hours.

Also Memtest has to hammer the cpu since its constantly reading and writing and comparing data in the ram. Now ram can't do that only the cpu has the power to compare data in memtest enviroment. And if the cpu is corrupting the 1's and 0's its going to spit back an error. Its just like prime a blunt instrument that can't tell you where the error is only that there is an error.

[Vio1]

if memtet errors in can be of two things: your ram, or your cpu since your ram runs through the cpu... it will show up in memtest. Thats why i suggest memtest first. If i can run seti (which uses 100% of my cpu for days on end, and my computer is on all the time, and I havent had an error, or rebot, or blue screen.... I dont care what prime95 tells me because my computer could not be anymore stable. You must realize that prime95 is just a cpu stress, and is not a be all and end all program. You most likely wont be running 100% load on your cpu 24/7 so if your computer runs smoothly, then its stable... or at least stable enough.

[jeffro]

I agree with the last reply. Perhaps that is something that can be called 'practical stability'. I'll take all this in and probably shoot for memtest and then Prime for curiosities sake. I don't think I'm going to mess too much with VCore and maybe just memory ratio if necessary, so if i'm still cookin' with the sandra test when I get home from work, I'll probably just leave it...until next time when I get more OC curious!

Thanks for all the reply's!

[Lan_Of_Malkier]

I'd watch the temps on air with that stock cooler above 3.2Ghz. I have about 1°~2° diff. in case/cpu/ambient temp at idle (this means fantastic case venting) and I get 50°~52° at load with the same HSF set-up. Invest in an sp-94~I did and can't wait for it to get here.

Refereing to the original post~which is it mate, a 2.8c or a 2.8E
It makes a world of diffy among o/c'n . I am assuming that it's 2.8c

Don't ever ever mess with PCI/AGP/HD....EVER. ;) Unless you want to replace alot of stuff.

Mess with your Memory all you want~just know what your changing and the effects of it~higher/lower can hurt rather than help if it's in the wrong combo. (see mem stickys)

Vcore depends on mobo, Vio1 has it right, don't go above 1.65 ever, and only go up to that if it's necessary. I'm running @1.5v and it loves it. 865 chipsets dont like high Vcore in most cases. Most successful 2.8 o/c's aren't above 1.6v~they don't really like the juice.

Annnnnd The Prime thing~bahh. We all know how stable Windows is (rofl)~and prime is a Windows Program. Nough said.

Good luck!

[jeffro]

Oops..my typo - it's a 2.8C

Ok..got home and sandra was still cooking. Feeling a little bolder, I did the following:

Upped FSB to 244 or so to get me 3.4GHz. FORGOT to throttle back RAM. Machine booted up to windows logon screen and that was it. Then I had a hard time even POSTing, but finally got it and then correct down to a 5:4 Memory ratio. Computer POSTed and booted into windows fine. Ran 2 passes on Memtest with no failures. However when I ran SANDRA burn-in, it hung after about 3 iterations. I upped the VCore to 1.55 and that didn't help.

Also set AGP/PCI to 66/33 and RAM timings to Corsair's published values.

So, I throttled back to 229 on the FSB and stock VCore and everying is rock solid. Ran Memtest with no sweat, ran SANDRA about 30 times through, Ran Prime95 for about 1/2 hour, ran 3d Mark and PCMark. All is good and I'm happy where I'm at as I don't really feel like pushing too close to the edge though I know I could achieve 3.4 with probably a little effort.

Max temp I noticed at load was 43 and its running 27 at idle. Case is really pretty good in that it doesn't insulate at all. My 3 80mm's are getting the job done.

Thanks to everyone for the help here! I'm pleased with my results!

[Lancelot]

You can say whatever you want about being 'practically' stable, but again if your system cannot run Prime95 for a couple of hours its just not that last few percent stable to have 100%. I can run my 2.8C at 250-255FSB 24/7 without problems, and it's running two SETI WU's most of the time too. But I need to back down to 243-245FSB to be able to let Prime95 run 24/7 (testing with one SETI WU running as well) So there is SOMETHING making a difference, and it's not just heat or Voltage...

[jeffro]

Yep..understand and it really doesn't make too much of a difference to me anyhow since prime is running fine and I really don't want to be that close to the edge....