low power and gaming doesn't really mix....imho
I have more or less the same unit which I use as an HTPC..I'm not a gamer but with the power draw of the unit alone + the video card, it's enough for the power supply to support it...
if you put in more ram and a bigger video card, that might max out or your p/s might not be able to support it anymore...you can try but you bear the risk of breaking the p/s and the components tied to it like the mobo and such...
Thank you for your reply, I do not game often but would like the option if I have the chance.
What kind of solution did you come up with for your unit?