On the other hand, I bought this card to replace a GTS 250 that was foolishly used in this same PC. That's reassuring, since my PSU seems to be roughly the same as yours, but with 19 amps on the 12 volt rail. The card specs have been updated to say that 300W is enough too. Its in my Dell and its worked flawlessly for 3 months.

patta016 You should be fine, I have a gtx 750 ti with a 300W PSU - Max 18A on 12V rail. I just wish I could find something stating the reason for the apparent change from 400w to 300w, for peace of mind. Before finding those comments, the only thing I'd seen stating the need for more than 300 watts was the box itself. On Newegg's product page for the card, I was able to find people referencing the need for a 400 watt power supply from back around February/March. He didn't ask me for the specific model of the 750 Ti (it's the 3751-KR), so there may of course be room for error there. I did make a phone call to EVGA support and the support technician told me that the box information hadn't been updated, and that the 300 watt minimum is correct. It's what came with my HP Pavilion p6310y, which I got about four years ago now. Zatunks My power supply is a Bestec ATX0300D5WC. Evidently that card required a 450 watt power supply, and while it worked great for almost four years, I'm pretty sure the power supply was one of the reasons it failed (there are probably two other reasons, but they're even more embarrassingly stupid errors on my part).

Bestec atx0300d5wc power supply open