Rebooting Problem with GeForce4 MX 420 and XP

[Guest_imported]

Okay... I've already bought this exact same card *except for the other one was AGP* and this one is a PCI... my other install for the AGP went as smoothly as possilbe... but I can't get this one to work. It's a GeForce4 MX 420 with Windows XP, and everytime I try to run anything that uses 3D it either freezes up or reboots, more often than not, it reboots. I've checked to make sure it's on it's own IRQ, and I have no idea what could be wrong with it. It's an EMachine with an onboard 2x 3d Card, and I didn't know if maybe that was it, or what. I've disabled it, but still the same problem. I'd appreciate any help at all, thanks.