Re: FSB speed
The Front Side Bus carries data from and to the CPU.
So if you are playing games like Doom 3 at high settings, you'll need a fast one so it can carry data from the graphics card and RAM. That's probably not the most accurate way of describing it, but it speeds up your system overall, basically.
Windows XP Pro 17" LCD Monitor (1280 x 1024)
nForce3 250 Chipset Athlon 64 2800+ w/ C'n'Q
1 x 512MB DDR400 CL3 SDRAM 40GB IDE 7,200rpm HDD (8MB Cache)
nVidia GeForce MX420 64MB PCI On-Board Audio