[XP] Unstable system - Dilithium Crystals?

My desk top system, the basic specs are in my signature, has run fairly reliably until recently. My problems began with the installation of a Hauppauge PVR card. As soon as I installed it, and the related software, my computer would shut off, then try to restart. When restarting, it would get to the XP splash screen then shut off and try to start again.
An endless cycle. Through experimenting, I found that if I installed the basic drivers for the PVR card, but not some of the additional software – specifically the ULead moviemaker software – I could get the system to run reliably.
Most recently, I bought a new HP multifunction printer. In the course of installing the driver/software for the printer I experienced the power-off failed restart situation again. I wondered whether the problem might be the Hauppauge card, so I uninstalled the drivers and all software and I physically removed the card. At that point I could only start the system in Safe Mode.
This evening I started the system and it booted up to Windows without problem. I then installed the HP drivers etc for the new printer. At the end of the installation, a restart is required. Of course when I went to restart I was back to the same old crash at the Windows splash, try again cycle. I don’t understand what the problem is. I looked at the System Info log and there does not appear to be a resource conflict. Any suggestions as to what the problem is and/or how to diagnose it?
Thanks for any help.

KM

I'd suspect an overworked PSU. Installing one more peripheral (especially one pinned to the Start menu so that it runs all the time) on an older computer will do that; older computers' PSUs (HP, Compaq especially) have a whopping 250W or so of power that is tapped pretty quickly.

Hauppauge is OK, but the drivers, UGH !
Nice price, but that is all.
Suggest getting something different.

Go to Control Panel>System>Advanced>Startup & Recovery>Settings and uncheck "Automatically restart". The next time it happens you may get a Stop error, which is much easier to troubleshoot. Post back what it says.

Thanks for the feedback, guys. I'll post back when I have the error message.

KM

Error code revealed that the problem was, in fact, with the D-Link USB wireless adapter I had added just prior to the Hauppauge card. I'v updated the driver for the wireless adapter and so far, so good. Havent put back the PVR card yet. We'll see what happens...