I'm a total newb to true overclocking, but I'm stuck on an AM3 system and I can't really upgrade anymore without completely starting over (I think ima wait for haswell). Anyway, here's some specs...
AM3 phenom II x4 955 currently at 3.8 ghz @ stock 1.4V (multiplier at 19.0, no bus speed changes).
Crucial 2x4 GB ddr3 1333 (cas 9, stock timings)
Xigmatek Loki 92mm CPU cooler (with artic silver set in for at least 5 months)
Antec EW 430W PSU
HD 6870 lightly OC'd
My current setup has good airflow, good mainboard temps, and is prime 95 stable with 62C at full load, but i want morreee .
I tried to OC to 4.0 GHz but it was unstable at stock voltage (1.4V), so I tried upping the voltage a bit, but that didn't help and made temps rise to 66C. Given my system and the info I've provided, what should be my next step? I haven't touched RAM timings or NB frequencies, could that be an issue? My goal is 4.2 ghz, is that reasonable? I don't suppose my PSU could have anything to do with it could it? It's a good one, it's got a total of 384W and 34.5A to throw at the 12V rails. Should I be dropping the vcore instead? That would seem counterproductive to me, but also seems like common procedure? But like I say, I don't know much about OCing.
Stock voltage is 1.35V not 1.4V. Your temps are also way too high. you shouldn't be going over 60°C Max. 55°C is an acceptable daily temp. Drop the voltage and start over.
There's no reason to do this though as the 955 is a good CPU and the 6870 is a midrange GPU which wont come close to being bottlenecked.
That PSU is really to small for that system. It will work. But you're running it right at its limit
I have the C3 stepping, thus the 1.4V. And yeah i don't like my CPU temps either. I think i'll lower the vcore and prime95 it overnight. I'll let you know what happens. And ahh, my PSU is a beast, it's handled everything i've thrown at it.
Hmm...well I turned it down to 1.35V and it wouldn't boot. So reset the CMOS and kept it at 1.4 for now. I reran prime 95 for a bit and got temps around 57 max, I don't remember how I got 63 now...maybe it was stock vcore at 4.0ghz or a different benchmark, idk.
At 3.8Ghz you are probably bottlenecked by your graphics card, depending on resolution. A different cpu cooler would probably help lower those temps also.
I remember reading an article somewhere a few years ago (might have been Toms) . Anyways I think the 965Be was top dog in the PhenomII line-up at the time...dont remember what stepping they were using.
It was an over-clocking article and they couldnt get any of them over 4Ghz and stable. They then said no sense in getting a 965, when 955 would do just as well. Of course, these days I see 4.2+ out of some of the Phenom II's, not sure if its a newer stepping, better coolers, newer MB chip-sets or a combo of the 3 making this possible.
Also, whats your ambient room temp? If you are in Arizona with no AC, you are gonna run warmer than a system in Canada in February.
well I messed around with it some more, jerry-rigged an 80mm fan onto the cpu heatsink, and the best I could do was 57C with 3.8GHz at 1.4V. I was able to get 4.0GHz stable with 1.425V, but at 62C max. So I notched it back down a bit.
Got a new case and reseated my heatsink. When i took the HS off, i saw that the paste didn't spread out as much as i would have liked. i use the "rice grain method", and apparently my rice grain on there was way too small. extended the grain to twice the length and applied it horizontally across the copper/aluminium pipes on the TI and wow...what a difference. 44C max with small FFTs in Prime95 at 3.8GHz with 1.3875V. insane. i wonder how far it can go?