Lockups!

Hey everyone im posting in need of some advice, i have a Athlon XP 2200+, 1gb PC3200 DDR Ram, 120gb HD, Geforce FX 5600 Ultra 256mb as well as the usual keyboard mouse etc and a Pinnacle TV Card.
Thing is, lately (since i have upgraded some parts) I am experiencing lockups while using windows and i am really unsure of what is causing the problem. Programs that appear to be affected are:
>Dr DivX
>Battlefield 1942
> Red Faction
> Internet Explorer (on rare occassions)

These applications completely freeze the entire machine in its tracks while in use, red faction and IE are recent additions to the list so i have ignored just bf and have refrained from playing it. Another game that appears to be starting to be influenced by this problem is Command and Conquer.

Im sorry i cant give much more details on the problem, but i cant be sure whats causing it myself. I have Windows XP Home with Sp1 and all updates installed, a fully updated antivirus and firewall and have just recently performed a full system scan and defragment. I also followed previous advice and used a memory testing tool you guys directed me to, this tool ran for ages and detected no problems with either 512 sticks. I am really at patience end! Please help! :(

What stuff did you upgrade recently?

The obvious thing would be to try and get new drivers (sound, motherboard, graphics, TV card), or, if you updated them recently, then to revert back to the ones you knew were working.

Also, you should try sticking in your old Geforce MX400 and trying the things that lock up. You might want to try taking out all the none essential cards i.e. the PCI cards to see if one of those is causing a problem.

If you still can't solve the problem you could back and wipe your hard disk drive.

Hope this helps.

Thanks ill give some of those ideas a shot