Cant put in new PSU! Is it me?

[palladin the II]

As i previously posted, I bought a 700x graphics card (best buy gift cards..came out to 20$!) anyway, i put it in hp media center (4200+ dual core, 1gb, 300w), my call of duty doesnt run as well, anyway, i cant seem to put in new 400 w psu i vought....the psu they have is impossible to take out because way the box is configured. any thoughts? 800x can run on 300w...do you think 300w will be enough for a while?

thanks...

 

[Gamingfreak]

even with a dual core that game isnt gona run very well with that graphics card unless u turn the resolution down, that power supply should be fine but a new one would be a good idea, also like i posted in your other thread make sure u update the bios and just go into the bios to make sure its recognized as a 4200+ dual core so ur getting what u paid for, if u dont know how to get into the bios start the compter up and just keep tapping delete and u should get into it