While it does say that you need a 300w psu the most important info is the amps and you need 22a on the +12v rail. If you can look at the psu that you have and see what it has for amps then that will tell you whether it will work with that card and if the amps is close then that will also tell you why it worked for a short while and now is not. If you hav 18a then the card may function for a little bit but not all the time and you don't want to underpower the card. Here is an example of a replacement for what you have now.http://www.newegg.com/Product/Product.aspx?Item=N82E16817338064
Athena Power AP-TFX35 350W TFX12V 80 PLUS BRONZE Certified Active PFC Power Supply for many HP Slimline System Upgrades/Replacement - OEM
$50.99 and free shipping.