MSI K9A2 wont post with TWIN2x2048-8500C5D R

[brains2200]

I cant seem to get this ram to post with more then one stick of ram in at a time. They all work in separately when just one is installed. But I i try 2 in or 4 in it the system wont post.

They are Corsair Dominator's. I trying bumping the mem voltage up to 2.1v. The other setting in this bios are all on auto.

I would like them to run at 1066mhz but right now I'd be happy with a post at 2gbs.

I have 4 stick but 2 are for another system.
They auto at 400mhz. So running at 800 then when just one in.

The system is

Phenom 9500
MSI K9A2 Platinum Bios 1.1
ATI Diamond 3850
2GB Corsair DDR2 8500 Dominators
Antec 500w Earthpower 80+
Winxp64

Could it be not enough power to the system? Is 500watts enough. I took out the ATI 3850 and put in a lower powered 2600xt 512 and it still did the same thing.

Was thinking 500w with this Antec 80+ would do well. Nice a cool. Low power consumation. I have a 550 Antec in another system but not sure I want to make a switch just yet.

Thanks

 

[akhilles]

The psu is overkill for that stock pc.

Is it your 1st AMD build? Cuz overclocking AMD isn't the same as Intel (easy). The only way to get the ram run at 1066mhz is to overclock it. It might introduce instability due to the erranta (you have to run the cpu at 100% load to stress-test the o/c) in the Phenom B2 (current batch). I think you should be happy if you can run the pc stable at stock. Some can't even do that.