FSB800? - That's Intel marketing speak.
the CPU runs at 200mhx FSB * 2(DDR) = 400Mhz
the Corsair XMS DDR400 = 400Mhz
Unless your overclocking (increasing the FSB) the DDR500 will be useless. Also, I've never heard of "Transcend DDR500" so I'd just go with the Corsair, as this RAM will overclock ok anyway
Whos round is it? Down that beer quick, smash my glass down, fall over the table - all rowdy and pissed