multiplier of 8 not stable

[mickeddie]

If I have my FSB at 360*9 (3.24ghz) my system is prime95 stable. If I change the multiplier to 8 and have my fsb at 400 (3.2 ghz) my system is NOT prime95 stable.

Do I need to make any other changes when changing the multiplier?

 

[pctan]

The difference between those two settings is your FSB clock rate.

You jacked it up and your system started revolting.

It could be your RAM...is it capable of handling a higher clock rate?
What sort of RAM are you using?

 

[Arrowyx]

If your RAM is DDR2-667 then give it 2.2v and set the timings to 5-5-5-15, sadly this is about all you'll get out of slower RAM like that. If it's DDR2-800 then there is some other issue, maybe a voltage level out of whack or something like that.

 

[mickeddie]

The difference between those two settings is your FSB clock rate.

You jacked it up and your system started revolting.

It could be your RAM...is it capable of handling a higher clock rate?
What sort of RAM are you using?

I am using OCZ platinum ddr2-800 pc6400, 4-4-4-15. The package says 2.1v which is what I have my vdimm set to.

 

[amdwilliam1985]

it could also be that your mobo can't take fsb at 400.

 

[Arrowyx]

Relax the timings to 5-5-5-15 and give it 2.2v and see if that clears up the problem. If not then check the vcore level, give it 1.5v. The key to overclocking is to reduce as many bottlenecks as possible. I have a feeling that the RAM doesn't like to run at 400FSB though. So like I said, make those two changes and then try to bench it. If it's stable then drop vcore back to stock and repeat. If it's still stable then you know it was an issue with the RAM. If it's not still stable then the only other thing to try would be lowering the FSB until you can make it stable.

 

[sruane]

If I have my FSB at 360*9 (3.24ghz) my system is prime95 stable. If I change the multiplier to 8 and have my fsb at 400 (3.2 ghz) my system is NOT prime95 stable.

Do I need to make any other changes when changing the multiplier?

You need to raise the FSB voltage. +0.10v should do it.

And you may need to lower your memory multiplier - to 2 if its at 2.5, for example

 

[mickeddie]

Arrowyx...I did as you suggested and it didn't work.

Sruane, I don't know how to change the memory multiplier. I'll check my BIOS.