Hi, sorry for the late response, could you post your full system specs? the cpu if possible, and it should be possible to run a HD 6450, for myself I am running a 7750 Low Profile in my 220W Acer XC600 computer, so you should be good too go.
Since I couldn't find anything about the topic, I am going to ask, does it matter what end of the DVI-D single link cable goes into what port? I am having the issue of where my display goes black randomly at random times, my video card is the Sapphire HD 7750 1GB low Profile, the computer is...
PSU is fine, I run mine on a 220W psu so he is fine, its just maybe the board may have a problem and the ram, you can't play at 720P as the game will use too much ram
None, as 400W is the minium requirement, so you are fine, a 7770 should also work, but you should not get any problems. And I know this from experince, I am running a 7750 with a quad core cpu on a 220W psu, why you may I ask? I also can't explain.