Overclocking my PC makes games run too fast!

May 2, 2010 12:51 AM

When I overclock my CPU, modern games run a little too fast.

I have a Core 2 Duo E7200 sitting on a P31-based motherboard (Gigabyte P31-DS3L) and running Windows 7 64. The motherboard drivers and BIOS are as up-to-date as they can be without installing files the manufacturer marked as beta releases.

When messing around with emulation or playing some demanding games I overclock it using Gigabyte's ridiculous-looking Easytune (I don't do it at the BIOS because 90%+ of the time the PC just sits in Windows with Firefox open). I don't change the multiplier (since I gather you can't) but turn the FSB from 266mhz to 333, and the core voltage from 1.12v to 1.18v.

This all runs fine basically indefinitely, with no scary high temperatures or crashing or anything. The only problem is in some games. It's most easily observed in Source engine games (Half-Life 2, Left 4 Dead 2, etc.) but we noticed it happening in Metro 2033 (which is annoying as it's a very demanding game).

Basically, lines of dialogue run together. As if overclocking turned up the game's internal clock, too, and it starts thinking that audio files end when they're only two-thirds over, so people talk over each other (and themselves!). It's possible that the character in Metro 2033 actually runs faster, too, but that's kind of hard to tell as I have to quit the game to return the clocks back to normal.

So, what's causing this? And is there a way to fix it?

posted by ArmyOfKittens to Computers & Internet (3 answers total)

Best answer: This issue is not uncommon when changing FSB speeds. Assuming it is actually an overclocking issue and not something like DirectX drivers or whatever, it is probably due to the other components not being able to communicate over the bus correctly with the CPU. There should be a setting in your BIOS or that Windows program to lock the AGP/PCI bus frequency to the default 66/33 MHz respectively. See here [1, 2]. I remain somewhat skeptical of a Windows based overclocking utility, even if it is from the manufacturer.
posted by sophist at 1:40 AM on May 2, 2010

Best answer: You might want to try rebooting with the new settings, see if that helps. It could just be a glitch caused by changing the speeds at runtime.

It wouldn't surprise me if windows sets up some of the more high speed clocks used for multimedia timing based on the bus clock when it starts up. Give it a reboot and see if it keeps doing it.
posted by delmoi at 2:23 AM on May 2, 2010

Response by poster: Well, that seems to work. After extensive fiddling with the Easytune application -- there is a field for PCI frequency, and although it's not alterable it's stuck on 33mhz anyway -- didn't seem to help, I tried overclocking at the BIOS instead. I've resisted this before because I've never been able to get Windows to boot with a BIOS overclock, but this time after changing the settings and pegging the PCI bus at 33mhz I went through the BIOS, found every option that claimed to automatically improve performance, and turned them all off. And now it boots at 333mhz and happily plays Doctor Breen's welcome speech without him talking over himself.

Now, to resign myself to a day of playing games. To test it. Yes.

Thanks! :)
posted by ArmyOfKittens at 2:56 AM on May 2, 2010