Overclocking

#161

Yeh the second I passed 3.8 it started spiking up somethin fierce.

#162

Same deal with me when I turn HT on, I went from high 1.2 volts to high 1.3s and ramped up the QPI considerably and it still wouldn’t pass linx (kept giving 124 errors which suggests QPI wasn’t high enough, wasn’t keen to push it any harder). Wasn’t too surprising considering nearly every screen shot I’ve seen of any C0 chip running @ 4.00GHz always has HT disabled. Every time I bumped the corresponding voltages up, it became a bit more stable, lasted a bit longer in LinX, but nowhere near 10 passes stable.

It was stable enough to bench but if it can’t pass LinX/IBT with max memory being utilised, it’s not truly stable. When I can be bothered again, I still think I may have a slight chance that I will be able to get mine stable at 4.00GHz with HT on, it just won’t be a 24/7 clock, strictly for benches.

#163

cmon nip you got the sick cooling and cant get a 4 ghz stable on a superior chip!

you call yourself the tech guru :huh:

bwahahahahahaha

#164

hah … on an early C0 chip … 4ghz is MASSIVE

#165

so. . . your trying to say our little i5 are better?

#166

Haha, there’s a big difference to having Hyperthreading on or off (4 cores or 8 cores). That’s why I clearly state whether my OC has had it on or off. There are also many more C0 chips under 4.00GHz than there are over that figure.

I can get 4.00 GHz stable with HT off (I use this as a 24/7 speed as per the sig), I even got it to boot at 4.2GHz earlier today, but as soon as HT is on, it gets too thirsty. Has nothing to do with my cooling though, the CPU would still be cool well over it’s safe voltage limits, like I said in another thread, I am voltage limited rather than heat limited. Since I’ve turned HT off, I’ve never seen it go over mid 60s, and that’s with C0 voltage.

Just to be clear, I never claimed to be the OE tech guru, I was given the title based on my sheer awesomeness, haha.

#167

Re-seated the d14 and spun the forward top fan around to be an intake to assist the big hsf …

Previous linX run :

New run linX top temps and a 1/2hr prime to see how the temps fare atm

#168

Definitely an improvement.

#169

not sure on the accuracy of it … but for i5 750 it really seems spot on … as the chip just needs juice every stp of the way in my experience … and the same with Johns from what i gather.

http://www.maxxpi.net/pages/special/vcore-characteristics.php

Still searching for the 100% difinitive that 4ghz is just not a 24/7 clock (my temp wise) … delving into IMC atm … might chip up a few notches to see what comes of it. Im also a little hesistant to run it at 1.168 when my ram is 1.65 … very fine line for the 0.5v tolerance imo … and 99.9% of 750 oc’s are all using 1.2+ IMC … just want to find out whether there is actual need for it … or they have done it from reading someone else doing it.

Higher IMC has produced lower vcore to maintain stability ive read … so it might be a case of which voltage is the cooler perhaps.

#170

Nice find Az. That’s actually really handy, it seems fairly accurate.

In my experience with the 940, higher IMC votlage doesn’t seem to impact the CPU nearly as much as high Vcore. This makes sense when you consider the size difference between the 4 cores and the IMC which has a much smaller footprint.

I think you should still be safe with your .482v difference between the IMC and DRAM, but I would probably touch the IMC up a bit to close the gap, it shouldn’t effect temps too much.

#171

1.225 was my initial bite and at same volts failed linX after 4 runs … interesting

changed the IMC to 1.2 and it reads 1.225 on the live bios reading … previously at 1.168 it would read 1.19~1.21 … hence my desire to get some windows software to see it when im under load. Dropped vcore 1 notch.

did a linX run and it failed on loop 9-10 change over.

I think ill go back to defaults and start the process again … i know i can hit 210 bclock with IMC at 1.168 set (didnt bother going higher … and were all 5 linx pass stable) … will see if there is any difference for 1.2

rather than stumble onto the good ground , ill work my way up to find it.

Gives me something to tinker with.

Ill also write a more detailed post for findings … all the way up to 3.8/4ghz

#172

whilst waiting for time on the w/e to do some o/c testing ( the desire is less now lol) i thought to put the sys to the test.

4.1 ghz failed @ 3/5 linX runs … and needed 1.33 volts for that… 84degrees on the hottest core … stopped then as i truly think it needed vcore and IMC to stabilise … so temps would have pushed my 85 absolute max i have set myself.

Pity as i was really keen to bench it :frowning:

didnt take a SS as it didnt pass … so not a real show imo.

So after that im 100% certain that i have found my best speed to be at … and the volts and temps are pretty spot on lol

43% oc will have to do … unless i can bullshit my way to making water cooling seem cruical enough lol

#173

I’d be wrapped with 3.8GHz on air.

#174

lol bad luck Az. Mine was already gettin close to 85 on 4GHz i think, so above that is outta the question. Once they hit their wall the voltage reqs get insane.

#175

course im happy with the oc … its huge … just sucks that the 4 and so on are just so close … yet so far lol.

I know i could get 4.1 prime stable … and at some point i will just to bench it for the sake of curiosity … but you always like to use linX as your temp marker … so you know the temp will never be reached by normal use.

Vantage pushes a machine almost as hard as prime from looking at the temps post benching.

while many push their rigs as hard/harder … i still will only leave 3.8 to run a bench.

#176

On my old system I use to have a very simple OC / monitoring tool that I could run in the background to keep an eye on performance and CPU/Vid card temps…be stuffed if I can find it now, anybody have any recommendations?

NVidia Geforce GTX275 // i7 // P6T

#177

for monitoring stuff : http://oceaniceagles.com.au/forums/showthread.php?t=7226

Do you have it o/c now ? or are looking to do so ?

#178

No its not o/c now…needed to see what the temps where atm…and apparently need to sort that out first…the highest core is currently at 90 with a load of 24% :rolleyes2:

#179

That doesn’t sound real healthy, I’d be reseating the HSF ASAP.

#180

HSF? …setting it to?:blink: