Currently over clocking my i7, never really tweaked the voltages during over clocks. Generally just increased the FSB to give me a little extra. So ill tell you what i have just now and would you be able to give any advice to a newcomer to this world. 4.2Ghz currently: CPU Muti 21 FSB 191 Vcore 1.23 DVID + 0.1V RAM 6CL So i under clocked the RAM to stop it exceeding the 1333MHz but it blue screened during my stress test on prime95. Does anybody have any advice on how else to hit around 4Ghz, with stability. The temps were not going over 80 think the highest it hit was 78C during the test. Is it better to increase the voltage rather than the DVID? Thanks William
Best to go for a basic setup first and then tweak once you have stability, but it probably needs a bit more vcore to be stable at 4.2 GHz. A simple 4GHz setup - BCLK 200, Multi 20, vcore 1.3v (most 920s/930s need less, but you need to rule it out), and clock the ram at under it's rated maximum. Go auto on your ram timings too - CL6 seems very tight. Leave QPI/DRAM, NB and SB voltages at auto for the moment - you'll need to play with them when you fine tune it - especially if you elect to increase BCLK and go for a lower multi; but auto won't do any harm for a basic 4GHz clock. [edit] further reading here - it doesn't matter that it's for a 920, the principle is the same (and there's only x1 multi between them). The article does over-egg the vcore - but I suppose they have to take into account that not all CPUs can do it under 1.3v.
When I Overclocked my I7 920/930 I used nearly always the same settings, only change was for my 950 which would clock higher. 920/930 Multi = 20x BLCK = 200 Dram Speed = 1600mhz or as close to it as it would go as the ram was 1600mhz but yours maybe slower or faster, and I manually set the timings. CPU Voltage = 1.275v QPI/Dram Voltage = 1.35v Dram Voltage = 1.65v unless the ram used less voltage Every other voltage was left on auto, and I ran prime for and if it crashed I upped the CPU Voltage to 1.300v, and tested again and if it failed again I went to 1.325v and tested and if it failed I bumped up to 1.35v but at any time if it passed for 8 hours, I dropped the voltage down by 1 notch and then tested again for 8 hours until it failed and then I bumped it back up and tested for 24 hours. With my I7 950 I followed the same settings as above except I could use a 21x multi with the 200BLCK, and it required 1.325v to remain stable for 24 hours under Prime 95. Some X58 boards/chips didn't like being overclocked, but most would atleast allow a 4.0ghz overclock using 20x multi and 200 BLCK, but sometimes you had to play around with them to get them stable.
1.23vcore seems low for 4.2ghz on an i7920 most require at least 1.3 if not 1.35 to hit that level of overclock
Could be golden but it's unlikely, but then again everybody has a different opinion of stable. CPU vcore has headroom because if you're not folding 24/7 then you can afford to lower it quite a bit... most apps don't see the CPU usage exceed 50%, especially with a hyperthreaded quad like the 930. In any case, your best bet is to start with a generous value (eg 1.3v for 4GHz, 1.4v for 4.2GHz)and work your way down (if you can). My 930 needs about 1.35v for 4.2GHz but only 1.275v for QPI; on the X58 platform I have always found QPI voltage the most difficult one to nail.
I don't know about most, but mine manages 4.2GHz (21x200) at 1.275v 1.23v would be spectacular and may be possible, but he needs to get it stable before trying for that.
Spreadie your 920 is a good un. My very best CPU was true gamer's 990X, and it could boot into windows at 4.5GHz with 1.28v but needed 1.34v for uber stability. For X58, anything over 4GHz with less than 1.3v is very good. And I've just noticed that the OP says 4200 at 191x21 which is not the case - 4.2GHz will be the turbo multi (22x) which is why the voltage can be so low, but it means your system is probably very unstable.
You can turn off turbo and manually set the 22x multi. The 930 is one multi higher than the 920, and I can set mine at 21.
Thanks for the info guys. I managed to get it stable at 4.1Ghz by dropping the FSB down at bit. Faster RAM might make life a bit easier for me.
