Hey i recently bought an ATI HIS 5770 although the card should be able to run almost all games on the market it can't. For example i can't run BFBC2 at all not even with lowest settings. This applies for most games. Is my PSU bottlenecking my performance or is it something else my PSU is 400watt. Could it be my CPU?
You've told us next to nothing about your system.
Some more detailed specs might help, including the make and model of the psu.