Re: O/C related help...
Intel Pentium 4 530J Prescott 800MHz FSB...it is 800MhZ.
There apparently are two kinds of FSB. One is set to 800MhZ or 1000MhZ, and the other is set to 133MhZ or 200MhZ. Your copmuter probably isn't overclocked, but knowing that it's a Pentium 4 Prescott helps.
Pentium 4 Prescott's like to overheat. Look at the reviews; people need to buy a new heatsink just to be able to play games on load.
Athlon FX-55 San Diego 2.6GhZ OCed to 3.0GhZ | Mushkin Redline XP 2x1GB PC4000 DDR500 3-3-2-8 OCed to 250MhZ | Seagate Barracuda SATA 400GB 7200RPM HDD | evGA GeForce 6800GT 350/1000 OCed to 425/1150