Have you tried older drivers? Try the 29.42 dets for XP (not sure about Linux).
Also, it could very well be an AGP problem in that your card needs more voltage than your AGP slot can provide. Modern motherboards haven't been designed to run AGP 1/2x cards. Try downloading RivaTuner and see if you can force the card to run at AGP 1x or 2x. If not, start saving your money and pick up a GeForce4 Ti4200 for $70.