You have a 533FSB CPU in there, it's likely set/running at some FSB:memory ratio like 5:4.

I'm not sure where in the BIOS that you can set it to something else, it'd be something like 'Front side bus:memory ratio'. Ideal setting is 1:1 but that would run your memory at 266. You could hunt down a 800FSB chip to run that there.

I'm not sure what FSB:memory ratio would be to run DDR400 with a 533FSB chip, maybe someone can chime in? 3:2?

Good points, gen_angry, thanks.

Never thought CPU's FSB would limit DDR's speed.

I can easily find a CPU with 800 Mhz FSB or even thinking to have Core 2 Duo E6700 2.66 Ghz 1066 Mhz FSB.

So in that case, would DDR run full speed (400 Mhz)?

-

deksar wrote on 2023-03-08, 17:12:

Good points, gen_angry, thanks. […]
Show full quote

Good points, gen_angry, thanks.

Never thought CPU's FSB would limit DDR's speed.

I can easily find a CPU with 800 Mhz FSB or even thinking to have Core 2 Duo E6700 2.66 Ghz 1066 Mhz FSB.

So in that case, would DDR run full speed (400 Mhz)?

I couldn't tell you tbf, I don't know how it would work with a 266 base FSB chip - have never used a DDR1 LGA 775 board with a Core 2 chip before. Hopefully someone can chime in there.

I just know that a 800 FSB chip should do 1:1 as that's 200 base FSB quad pumped, so it matches.