If I was to run FSB at 166Mhz, do I set memory speed in BIOS Advanced Chipset Features to 266Mhz or 333Mhz?

333 MHz because it is DDR SDRAM ... 333 MHz DDR SDRAM has a clock speed of 166 MHz in both output and input, so they add up to 333 MHz ...

from the manual of the motherboard,
a 333fsb cpu actually require ddr ram 333mhz
if using 266mhz ram, does works?

I have the GA-7VRXP I bought PC-2700 DDR RAM which runs at 333Mhz, I also have an Athlon XP 2200+

My CPU is locked so all I can do is FSB overclocking, All I can do with this CPU on this board is 1.9Ghz that's with 141Mhz FSB. I think this is really bad since the CPU only gets me 100Mhz more. I have a Volcano 7+ heatsink. I don't think the CPU gets that hot (45 under full load. I have seen 50+ and stable on other boards), I believe is my Ram the problem. With a 141Mhz FSB my RAM can't run at 333Mhz, all is able to do is 266Mhz (Sandra shows is running at the same speed as the CPU FSB 282MHz). Oh and to make this stable I have to use the 10% option in the vcore.

CPU Vcore 1.81v
Aux Voltage 1.36v

I belive this is very bad since is only a 100Mhz increase and only 8Mhz more on the FSB.

So I got to the conclusion that with really good RAM this thing should go easy to 2.0Ghz with just a good heatsink (air cooling)

I will clarify some more. I have Gigabyte GA-7VRXP, AthlonXP 1800+ (soon to be unlocked) & 512MB Samsung PC2700. In Advanced Chipset Features in BIOS there is setting for 266Mhz, 333Mhz or Auto DDR Speed. In other words with FSB at 133Mhz, 266Mhz sets ratio 1:1 and 333Mhz setting sets ratio 4:5. At the moment I run async 133/166. When my Athlon is unlocked & I wish to go up to 166/166Mhz do I leave the setting at 266Mhz to run 1:1 ratio with CPU? or do I set 333Mhz?? Or should I leave on Auto? Probably only person can help me is someone who has the same board with unlocked CPU running FSB 166Mhz.

Try running the updater on SiSoft, after the update my ram shows itself as PC2700, thats the rating Corsair set the XMS3000 to, appeared as PC2100 before.

its not the ram but more the processor. I'd unlock the cpu if I was you and then up the fsb and have a lower multiplier.

But that's exactly what the man is trying to do...

I'm facing the same question myself, as I also have the 7VRXP and a 1700+, and was thinking of unlocking the prosessor to raise the fsb to 166.

I sent e-mail to Gigabyte about this and they only said something like "We don't support any overclock things", (funny as they send the EasyTune program along with their mobo's which is ment for overclocking...=)

I've put this question in a couple of forums, but no one seems to have a 7VRXP and an unlocked CPU.

So it seem we'll just have to try and see for ourselves =)