I have just built two new rigs, inspired by Issue 83, building a futureproof PC: Rig 1 Coolermaster HAF932 case XFX Black edition P1-750-NLG9 PSU Intel Pentium G6950 processor Artic Cooling Freezer 7 Pro Rev 2 cooler ASUS P7H55-M motherboard 4GB Crucial BL2KIT25664BN1608 memory EVGA GTX465 graphics card Windows 7 Prof 64 bit Rig 2 Coolermaster HAF932 case XFX Black edition P1-750-NLG9 PSU Intel Pentium G6950 processor Artic Cooling Freezer 7 Pro Rev 2 cooler ASUS P7P55D motherboard 4GB Crucial BL2KIT25664BN1608 memory Palit GTX460 1GB graphics card Windows 7 Prof 64 bit Both are primarily folding rigs as my mum died of breast cancer last year and I wanted to do something more, though I have been folding since 2004. The first rig overclocked to ~4GHz using the exact method in the mag , but the second rig BIOS was slightly different and wasn't having it! Both graphics cards are producing about 10150 to 10350 ppd and the overclocked CPU is producing 2700ppd, but the standard clocked CPU is only 1790ppd. Any advice on how to proceed as I know the CPU will run at 4GHz rather than 2.8GHz, if handled properly? btw, well impressed with GTX460!
Does it freeze on boot, blue screen or something else. Every chip is different, some don't like overclocking at all
Every chip is different, some don't like overclocking at all This is very true, as an experiment you could try swapping them over, if it clocks up then you can rule out a moody chip and start looking in to the bois for options that you might have missed. The CPU you're using is a right little hooligan of a chip and I'd have thought it would have hit 3.5 at least.
Hmm I was really thinking of getting the G6950 chip for its overclock-ability and the fact the new architecture leads it open to upgrades a few years down the road... bit put off if its a lucky draw as to whether the chip you get will accept decent overclocking :/ Anyone else had similar woes?
It's quite normal, some i7 920's will struggle to hit 3.7 with loads of volts and everything else turned up. Then the next 1 will go to 4.2 with more to come and hardly any increase in the voltage. What you have to realize is that Intel builds a chip to a certain standard the ones that behave better become the higher grade chips ie: A 920 passes all the tests and the the next one performs better that will be a 940 and so on. As long as they all perform to a set standard Intel doesn't give a crap how well it overclocks. Amd do the same thing by disabling bad cores on quads to make dual core chips. If they didn't do this , imagine how many lumps of silicone would end up in the bin just for not making the grade and us, the paying public would probably end up having to foot the bill for it all.
Thanks for the explanation Jeff, I understand why it is that way, but it does make buying a cpu for overclocking a bit of a gamble doesn't it?!
Pretty much, I've had some good 1's and some average 1's. My sons AMD X2 245 will run quite happily @3.8 with out any messing about with the voltage and there's more to come if needed, it's hit 55 degrees on prime 95( it is water cooled though). I reckon it could go to 4 GHz, yet some people have just about got 3.5 stable on these. My i7 940 should go beyond 4 GHz, so as you say it really is the luck of the draw. Looks like you've got a good 1 and an average 1. The thing is, I know it's PAIN but try swapping them over it might be the board thats at fault, at least that way you'll know for sure.
er the second PC which im guessing is the one that doesnt oveclock well is using a P55 board not an H55 which is much better at overclocking i3/G6950 than a P55. thats your first issue. second as already said not all chips are the same so you probly wont get the same overclock even from identical machines. There are just too many variables in the manufactuering process from the CPU to the motherboard to garantee the same overclock from every chip.
Thats a good point, but I wouldn't have thought that it would hold it back as much as it has done. If the CPU would have hit about 3.5GHz I would have thought fair enough, but 2.8GHz is well low.