Overclocking AM2 boards

[Daston]

Hi guys

Are the rules for overclocking am2 chips the same as Skt 939? IE increase fsb speed and lower ram speed to compensate? Looked at the bios for my Crosshair motherboard and it seems to have lots of different options for the ram timing but no method of chaning the speed (ie I used change my old ram from 400mhz to 333mhz).

Does anyone have a quick guide or can someone give me some pointers?? Idealy I would like to get 3ghz out of my cpu.

Spec

Asus Crosshair SLI
AMD X2 FX 62
4gb OCZ SLI 8500 DDR2
2x 8800GTX
Soundblaster HI-FX Gaming
Enermax Galaxy 1000W PSU

500 marks behind the fastest score on 3Dmark 06

[MONKEYMAN]

Pretend its a 939 board, you overclock in exactly the same way.

The RAM gets a bit warmer then normal DDR and upping the HT voltage slightly seems to actually help with high HTT speeds on the AM2 board I have where it made no difference on my 939.

[Daston]

Right I have had a little play around and managed to get the core to 3.15ghz this was from upping the multiplyer to x15 and the core speed to 210mhz. My RAM is running at 667 and in CPU-Z shows its at 350mhz so still a little way to go before its at its peak.

Now the problems I have are this, as soon as I increase the core speed anymore windows does not boot and the PC restarts. I have tried to up the voltage a notch to compensate but this then just forces the PC not to post and I end up having the clear CIMOS.

Last question I have OCZ SLI Ram, now in bios it says something about "SLI RAM frequency" and "SLI RAM CPUOC %" any idea what those do??

[MONKEYMAN]

I cant help with the RAM question but I can help with the other...without raising your core voltage substantially you will not get much over 3GHz, the fact you have achieved 3GHz+ is good.

However lowering your HT multiplier to 3 will help with high fsb issues and could well be the answer to your problem, I would try that first and then start slowly increasing core voltage keeping an eye on temps.

[Daston]

ahhh forgot about the HT multiplier! cheers will give that a bash.

[Daston]

This is interesting,

Booted my pc into xp last night with the above settings and got a blue screen and reboot, however Vista booted fine

[Meridian]

The main difference is that AM2 boards can run much higher HTT figures: where S939 really didn't like going over 1000, AM2 will run up to about 1250.


In the case of the Crosshair, most of the RAM options are useless, because like all A64 chipsets, the RAM speed and settings really aren't important for anything except running SuperPI as a benchmark. Or Sandra memory bandwidth. In the real work and most more general benches, only CPU speed matters, is it did with S939.


At the risk of boring the bejeezus out of you (and hoping mods don't take this as plugging the opposition), there is a thread here on what i did with my Crosshair. There's a fair amount of info on what got changed, and what effect (if any) it had. Goes on for a bit though...


M

[cadaveca]

lol. only nforce chipsets didn't like HT speeds over 1000mhz. But yes, AM2 boards tend to go a fair bit higher, with ease.


Got an update, Daston?

[Daston]

Ok currently running at 3.2ghz (x15 multiplyer and 210mhz bus speed)
The HT link is at 1050mhz.

Anything over this causes my pc not to boot. The current voltage settings are 1.264v and I am unsure how much I should increase it. Ram is sitting at 350mhz

[MONKEYMAN]

Im running my am2 at 1.5v fine...

[Meridian]

As the man says, start by increasing Vcore, but watch the temps. If this makes little difference, try dropping the RAM divider.


M