Hey there,

I recently bought OCZ DDR2 PC2-6400 Platinum Revision 2 RAM:
http://www.ocztechnology.com/products/memory/ocz_ddr2_pc2_6400_platinum_revision_2

I have Asrock 775Dual-VSTA mobo and here is the website:
http://www.asrock.com/mb/overview.asp?Model=775Dual-vsta

My question is that even though I understand that my mobo supports DDRII667/533, what are the best setting for the RAM to run on my system ?

These are a couple of CPUZ screenshots for the DEFAULT settings my mobo detected for the RAM.




Thanks in advance

Please correct me if I am wrong but is it not ok to run a high-end RAM on slower frequency for relatively old computers ? :suspiciou
For example, PC3200 memory should work fine in a system that takes PC2100 or PC2700.

Not true. He can run the 800 mhz RAM on the system; it just won't perform at that speed and frequency. He won't be able to optimize the benefits of the faster RAM, but it will work.

So is it okay to crank up my frequency to 677 then yes ?

Use the 800 mhz and leave everything alone. It clocks down.

Yes and No. It all depends on the RAM. Some RAM will take it and so will some computers. Yoiu can try it, but if the computer won't take it, you'll have to clear the CMOS settings (jumper on the mobo). Additionally, if it's cheap RAM,you stand a chance of frying it, but with OCZ, it shouldn't be a problem. If the system becomes unstable (based upon the mobo), you may have to reboot and go into safe mode to reset the bios.

my bios does not have an option for 800mhz
should I be using tools like memset to force 800 ??

I've changed timings to 4-4-4-15 with DDR2-667


but now I am not sure about the fsb/ram ratio.. is 3:5 ok or can I make it 1:1 ?? does it even matter ??

also, is 3:4 better (which I get with DDR2-533) or 3:5 better (DDR2-667) ??

Agree with Codex Computing. Let the bios set the RAM speed and timing. If 667 is the fastest RAM the mobo will take, it will clock down (automatically) to 667. You won't be utilizing the RAM to its fullest potential, but it's better than frying your hardware. Just leave it alone.