4GB about 675mhz 0r 2GB about 800mhz

"How can I configure this 4 banks to have the best performance? "

In the BIOS.

^what Nikorr said. 4GB would be preferable. The difference between ddr 2 667 and 800 is in most cases small.

If you use both sets of ram, all of them will run at the lowest speed of 667 mhz.
Put the 667mhz ram in the first set of slots then the 800 mhz in the second set of slots.

Although your system (x32) does not fully use 4gb, it might use as much as 3.5gb, depending on the motherboard and CPU.

If you hear any beeps or there is a lag, it is better to just use the higher mhz (despite what others might say) as long as the motherboard ram specs allows it. Don't bother with overclocking or underclockng, you will just wreck the ram, leave as default unless you really understand the consequences.

If you want a more definitive answer, provide your CPU and motherboard model numbers, and manufactureer and specs.

Also, in most cases,

the mobo will set all the RAM sticks to the lowest speed RAM stick that is inserted.

That way it works in the flex mode.

Not good for overclocking : )

Thanks for everyone.

I increase voltages a little, 2.0v instead of default 1.8v

Now the 4 sticks is running at 391mhz 5-5-5-16 CR2. I'll test the stability for sure.

CPU 2750mhz, memory set to 667mhz divisor what results 391mhz in my system.


Problem solved.

Increase a little, is by 0.05v

2.0v is way to much.

Try to get it lower. Its better at the lowest possible when it is still stable.

Post what mobo do u have?

And the CPU.

Universal Abit AN-M2HD and Athlon x2 4200+ @2750mhz default voltage.

This mobo is really crazy but I'll try to get the memories at 1.9v.

I set 2.0v cause I saw some mobos increasing ddr voltage by itself to 1,85v or 1,9v.

DDR2 800MHz, PC2-6400
maximum RAM capacity: 8GB

Thanks for everyone. Problem solved.

Best answer selected by Gabriel4TH.