Buy the card and try it. If your system won't power up then you can pull the card and get a better power supply.
The 300W is probably the maximum it would need, and that is if you're pushing a lot of heavy duty 3D stuff through it, like in a video game.
For desktop use (e.g. browsing, running Excel, etc.) and watching videos, the board won't consume very much power. Like 75W not playing games, 125W-150W playing games.
Buy the card and try it. If your system won't power up then you can pull the card and get a better power supply.
The 300W is probably the maximum it would need, and that is if you're pushing a lot of heavy duty 3D stuff through it, like in a video game.
For desktop use (e.g. browsing, running Excel, etc.) and watching videos, the board won't consume very much power. Like 75W not playing games, 125W-150W playing games.
You might be able to bring your PC into a store, like enuinc.com, and have them put in the card and optionally a new power supply. When you take the machine home, it'll be sure to work.