Hey guys, I recently put together my new build and just tried overclocking today. My system specs are: i7 920 D0 Gigabyte EX58-UD5 6GB Patriot 1600Mhz Sapphire 5850 I got the i7 920 to 4.0 Ghz, but the prime95 temps of 85C scare me. I followed this guide: http://images.tweaktown.com/imagebank/Core i7 920 oc 4G 2008.12.12_(ENG).pdf I have the Bclk at 200 the QPI link speed at x36 uncore frequency to x13 cpu vcore to 1.400000 v qpi/vtt voltage at 1.515v I also have the ram at 1.64v running at 1600Mhz I tried just changing the Bclk to 180 to get 3.6Ghz, but then I couldn't get the ram to run at 1600Mhz, because none of the multipliers in the bios let it be 1600, only lower or higher. The idle temps are only 40-45C, its the load thats worrying me after only 10 min of prime95 I have only adjusted the values mentioned above. Any advice is greatly appreciated
what cooler do you have? your vcore seems a little high. which thermal paste did you use? try this thread for some of our settings: http://forums.bit-tech.net/showthread.php?t=178125
With the settings i mentioned above, after about 5 minutes of prime95 the screen would just freeze. I went into the bios and selected the cpu at 180 for 3.6Ghz but now the ram only runs at 1440, is that normal?
the memory freq is worked out by multiplying the BLCK (in that case 180) by the memory multiplier (x8) which makes 1440. so yes it is. have you got LLC (load line calibration) enabled? because you shouldnt have to run a D0 920 at 1.4v to get 4ghz.
also additiionally your uncore frequency is far to low this could be causing instablity. as a general rule of thumb it should be x2 RAM freq + 1 multiplier. so yours is 2600mhz but it should be 3400mhz (x17 with 200 baseclock) as refereance my i7 920 D0 with a X58-UD5 is @ 1.3V @ 4Ghz with 200 baseclock and 1600mhz RAM. i get about 77-80C under load and my room is pretty warm
I made some adjustments and these are the new values I'm using: uncore x17 bclk at 191 vcore at 1.315 qpi at 1.375 (the last one before the pink numbers start) the temps have dropped and the system is much more stable on top of being noticeably faster. I ram prime95 for 7 hours and everything was fine, thanks guys and <3 bit-tech
glad we could help. personally i didnt like the 4ghz @ turbo method, i preferred having BLCK of 200 so it was 4ghz at load, 2.4ghz idle (x12 multiplier). just feels like theres less faffing around with turbo mode.
a quick update, my previous post should have read a bclk of 180 which passed prime 95 for a few hours. I tried upping it to 191 or 200 with the same other values and after 15min to an hour of prime 95 the screen just freezes, but it should be noted the temps aren't unusually high, about 70C. Also, at idle a bclk of 191 was fine, it didn't crash for 12 hours, but under any load, after about 25%, it would freeze the screen, but no BSOD or anything like that. Using windows 7 ultimate 64. Am i better off just staying with a bclk of 180 @ 3.6Ghz? Also for the ram, you said above running it at 1440Mhz at a 3.6Ghz cpu overclock was normal, but how much performance am i losing by having the ram running slower, and is there a way to still get it to run at 1600Mhz?
I'm currently running my DO on the Extreme; pretty much your board with extra cooling. I am running mine @ 4.2ghz 24/7 at about 1.26v for the CPU. I'm at work at the moment, but I'd be happy to make a note of the settings that I am using and post them up for you. I know that no two setups are identical and what works for me might not work for you, but it may give you an idea of what to tweak. I'll be honest though, I have turned off Hyperthreading for day to day use after reading this thread. In most games I play (older ones like BF2) it's actually better for me with it turned off. The drop in temps is also a bonus, but as my system is watercooled they aren't an issue. If I do use something that utilises HT (GTA 4 works better with it on), I just re-boot and enable it. My settings work just fine with HT on or off.
