Widescreen Gaming Forum

I think I've finally settled on a Core i7 overclock. It's a little warm, but I think I can shave a few degrees off buy taking the voltage down a few notches. We'll see. Failing that, I can get some stronger fans, as while quite, the fans I'm currently using don't push a whole lot of air...

For those who read the Latest Acquisitions thread, you'll remember that I had some problems getting 3.6GHz stable, and so pretty much chickened out for the time being and backed off a mile.

Since then, I got bored, and got tweaking.


1.35v (BIOS) 1.31v (CPUz) 1.298v (Real) = 4.18GHz boot into Windows. Well, actually, 1.24v (CPUz) got me this as well, but it'd crash as soon as I opened Paint. This BSOD'd with LinX after about 15 seconds... and as I don't want to push the volts any higher until I slap I waterblock on, I backed it off. Actually, come to think of it, it might be stable here if I just disabled all the throttling features. However.


3.8GHz is solid. A bit warm, but solid.


3.8GHz loaded with Prime95. Hour shot. Got bored after that and wanted to check LinX stability. It's about 3*C warmer than I really want to see it, but if I take Vcore back a little it should drops temps a bit.


30 minutes of LinX (will do longer tomorrow) testing the CPU/RAM. To note: my 3.6GHz wasn't stable because LinX would crap out after 9-11 minutes. This is apparently because there isn't enough QPI voltage, as when I tweaked that, it didn't BSOD on me. Also, the QPI multipliers are quite finnicky - once I realised that quirk, my 3.6GHz was stable. But 3.8GHz is more interesting. :D

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Might put it back at 4GHz, see how it handles the temps (and stability). I'll try 4.2GHz if I watercool it I think.

But there we are. Once the QPI multiplier thing was realised, clocking Core i7 became a lot simpler. The temps aren't quite as bad as they look as they're core temps, which are higher than the reported 'Tcase' of the CPU (hell, the Gigabyte Easytune monitoring utility and the BIOS report the CPU temp as 16*C at idle and 54*C loaded with LinX.

So. There we are. 3.8GHz.

With all that talk about fans, I gotta ask what aftermarket CPU cooler you're using? I didn't notice you mention one at all.

Here's a pretty good video guide on OCing an i7 CPU btw. It gets kinda funny at the end too. It's taken from some pretty knowledgeable guys at forums like XtremeSytems.org.

http://www.youtube.com/watch?v=iwbzQblRQ7I

I'll probably go with a 920 or 940 i7 on my next build around year's end. Which one I get will depend on the pricing on the 940. I don't think I'll go above 4GHz, and I know the 920 can go that high, but the 940 is a higher bin chip, so it should remain stable longer at that speed.

I'm still stock at 2.6GHz. I think I'll have to tweak mine soon. I wish someone made a low profile fan for the i7. Can take anything over 100mm tall in my Antec case.

Yeah, the heatsink is a TRUE120 with fans in push/pull. This thread was only really made so I didn't keep cluttering up the Latest Acquisitions thread. :lol: I lapped the heatsink - not a perfect lap, but infinitely better than the stock finish. It was keeping it really cool on the bench (10*C above ambient) but in my P180 the heat just builds up. As I said, the fans I've got in it just don't shift air fast enough.

Thing I've found is... you can take advice from others all you want... try their settings out with identical kit and everything. Every time I tried using someone elses 'known good' settings, all that would happen is the board would fail to even POST.

Unless you're desperate for that 22 multiplier instead of the 20 of the 920, I don't think the 940 is really worth it... at least in the UK where it's twice the price of the 920 for an extra 266MHz.

i7 puts out a lot of heat when it's overclocked. Well, actually, if you load it at max it puts out a lot of heat at stock, too. On an open bench it's controllable a lot easier than in a closed case situation. Any situation that rides the RAM hard pushes CPU temps up quite a bit too, due to the IMC. The Athlon64 never had temps increase from hard RAM use as much as this in my experience of those chips. Volts needed to get i7 to 3.6GHz is barely any above stock - some chips will do 3.6GHz on their stock volts. 3.8 needs a little push from what I've seen, and the required volts (and therefore temps) really start to climb above that.

As a note - I could take 10*C off those temps by turning off HyperThreading. I tried it. However, that has an impact on encoding times (a fairly significant one as it happens) so turning of HT is an imperfect solution for lowering temps.

Do any of you i7 owners own GTAIV for PC? Can you see any difference in FPS before and after? My frames are chugging in Triplehead and I'm really frothing at the mouth for a new CPU.

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EVGA GeForce GTX 970 SC ACX 2.0 3.5GB | 3 X LG Flatron 24EA53VQ in Nvidia Surround | Optoma HD20

http://www.pcgameshardware.com/aid,672004/GTA-4-PC-Intel-Core-i7-far-ahead-of-Core-2-Quad-in-CPU-benchmarks/Reviews/


Doesnt; lsit y our q6600 but it gives a pretty good idea of what you coudl expect.

Thing I've found is... you can take advice from others all you want... try their settings out with identical kit and everything. Every time I tried using someone elses 'known good' settings, all that would happen is the board would fail to even POST.

Unless you're desperate for that 22 multiplier instead of the 20 of the 920, I don't think the 940 is really worth it... at least in the UK where it's twice the price of the 920 for an extra 266MHz.

Well you generally get more similar results to what most others do if you start out with water cooling or a case with high air flow. The P180 was good for it's time, but you need something more like their P193 with that kind of gear. The case I'm liking right now is the Thermaltake ElementS. It's very well made, very affordable, and the airflow is so good there is very little change between idle and load temps. It's also pretty quiet and has dust filtration.

Also, the 940 may be physically the same chip as the 920, but being a higher bin spec means it's passed more stringent thermal imaging testing, so it doesn't leak current through it's transistors as bad and thus less heat produced. Chances are a 940 will run more stable at higher speeds. That's why they cost more, not due to a mere 2 digit higher multiplier. The TRUEs work pretty well to manage that heat though. I think it's more your case than your CPU cooler.

BTW, when you ramp up your bus frequency are you doing it in no more than 10MHz steps?

Also, the 940 may be physically the same chip as the 920, but being a higher bin spec means it's passed more stringent thermal imaging testing, so it doesn't leak current through it's transistors as bad and thus less heat produced.

The 940 is NOT the same chip as the 920 right now, Its getting phased out and getting replaced by the 950 for the same price with a higher clock speed, using the same chip that the 920 has now.

Well, I just took the Vcore down again after my attempts to get 4GHz. 3.8GHz is currently stable (although it's only after fifteen minutes) of LinX at the same votage I had 3.6GHz at. 1.275v (BIOS) 1.21v (CPUz, idle) 1.184v (CPUz, load). I found LinX tends to BSOD after <2 minutes if there isn't enough Vcore, so I'm hopeful this is good.

The other thing the votage drop has done is take 10-11*C off the load temps, and a good 8*C off the idle temps.

I'll post a screenie when it's done 30 runs... if it makes it. It looked like it will. GFlops has gone up - 49.87 is the top now, as opposed to the 48.2 or so it was yesterday. So far, the whole system is cooler, although I don't think temps have maxed yet. Still, I very much doubt they'll break 75*C on the cores, as it's really floating on 70-71*C right now.

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All the 940's are C0 stepping chips. The 920's used to be C0 step, but are now D0. The 940 is being replaced by a D0 step 950 (@ 3.06GHz stock IIRC) and the 965 is being replaced with a D0 stepping 975 (@3.3GHz IIRC)

I guess binning procedures have changed since I last really looked at them, then, really.

Well, that's it... unless I feel desperate for another 200MHz, I'm gonna stick at 3.8GHz.


Shot during. LinX hammers a system so hard that Windows 7 struggles to keep the screen refreshed - there was a minute or so in that 50.05GFlop run that I thought it had frozen... each time I got a really high reading, the screen would either get really sluggish, or not update for a few seconds. Shows just how hard LinX can push, really.


LinX run complete without errors in 1h20m35s. The 50GFlops is an 18.5% jump from what I was getting at 3.2GHz... which is an 18.75% clock boost. RAM was running at the same speed for both, so that probably accounts for the not quite linear scaling with frequency.

System is now idling @ 41-41-43-38 on the cores, which is about 6*C hotter than stock with all the throttling functions enabled. I don't think 41*C is too bad at 3.8GHz, when it's 35*C at 1.6GHz. ;) Idle temps go up to 47-47-49-44 if I turn all the fans right down to minimum. However, I'm not going to do that often as the fans don't annoy me that much (a lot quieter than the fans in my old system at max) and the GPU fan is always at 100% so I can hear it if I turn all the others down. As the 'whoosh' of air is less annoying than the GPU fan whine, I'll stick to the 'whoosh'. :lol:

Despite RealTemp saying that temps maxed at 74-74-72-70, I didn't actually see it hit 74*C - that occurred in one of the 'slow refresh' moments and it usually floated around 72*C +/- 1.

I'm happy. That's faster than I wanted it, with temps I think are acceptable (<75*C) on the cores. My Core 2 Quad hit 70*C on the cores when it was running at 3.4GHz, so I don't think that's bad at all. I finally seem to have got my hands on a half decent overclocking chip. :lol:

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Did check out that Thermaltake Element S case... I'm firmly in the 'plain simple understated cases' camp (like the P180 and the Silverstone TJ07) I think - it's not as bad as some cases I've seen, but I still thought it was ugly. It's got some interesting design ideas, but also I need dust filters everywhere on this rig, as the room it's in is fairly dusty.