i have an hd radeon 6450 (1gb ddr3) and im debating whether to buy a new psu or just leave it as it is and just use the graphics card but i dont want to fudge up my computer (i have an hp pavilion a6112n) i upgraded the ram to 4gb if that helps with anything
The 6450 requires a minimum of a 400w power supply to be in your system , you can always try to run the card with that power supply and see if it works. If it doesn't then it will shut down or give bad pisture quality but it shouldn't ruin your system. However you could upgrade the psu to 400w and not have to worry.
There are a few to choose from and the choice naturally is yours to make but you do want to stay away from the noname brand and try to go with the proven quality brands. Antec , Silverstone , Corsair , Enermax , Cougar and Seasonic.