Nothing is assured, but stay under 127GB to be sure that most machines of that era will work. Also a key factor is the POWER SUPPLY may need an upgrade since... it was selected for just what was in the box and not much else. And as the years pass, the supply degrades and can't supply what it used to.
Dont' be surprised if it starts to go unstable with 2 hard disks and a spiffy 3D card.
Bob
Hello everybody. My computer is a compaq 5bw220, win xp, intel celeron 633mhz. 384 mb ram. I want to upgrade my computer. I want to add a new video and sound card. But the computer came with video and sound built into the mother board. Can I still add these items. I also want to add a second hard drive. The system came with a 15gb one. How do I know if I buy a bigger hard drive then 15gb the computer will recognize it. Thank you.

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