Desktop

After installing WinXP did you update your drivers?

Most freezes at boot up could be narrowed down to hardware drivers that need to be updated,check the Video card see manufacturers web site for updated drivers to card to support Windows XP or Win 2K

Check the Memory to make sure they are seated in slots properly

1) Although the CPU and memory was on the other motherboard when that board is burn, since the system boot up fine and run fine (accept the freezing problem), I assume the CPU or memory aren't damaged.
2) The VGA card was also on the board when theboard is burned. Since it is still working, I assume that it isn't damaged.
3) When first install Windows XP, the graphic is poor. I tried update the VGA card drive, but that didn't help. I end up going around the problem by disable hardware acceleration (in Display Properties).

I had faced such problem recently on an XP Home. You can use the 'msconfig.exe' utility to try and fine the bottleneck.
Heres how to use it : http://netsquirrel.com/msconfig/
Hope this helps.

4) I notice that the system seem to freeze sooner when I open many programs. It runs for about 10, 15 mins when I open 5 programs and runs for 30, 45 mins when I only typing in MS Word.

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