Hey guys, I have two computers, one is my every day computer equipped as follows:
Core 2 Quad Q9550
Geforce GTS 450
The second one is an Optiplex 755 that I got for free from a small business I consult for who was upgrading, and it's currently equipped as follows:
Core 2 Duo E8500
I set up XBMC on both and it works flawlessly on the Core 2 Quad, I can even fast-forward a 1080p movie at 16X and there is no visible pixelation or distortion. On the Core 2 Duo, 1080p and 720p movies will play for maybe 15 seconds, freeze on a frame, and then stutter and catch up to the current location maybe another 15 seconds later. CPU usage is maybe 20%, and just for kicks I tried swapping in 8GB of RAM to no avail. I am looking to try a more powerful graphics card next, but is there a possibility that the CPU is too weak?
I would try to run a temperature monitoring program on it while it plays that, or even better while it does some CPU-intensive stuff. If temps are too high, try re-applying the paste.
OTOH, the GPU might be too weak for it. Also, make sure the PSU can handle the full load.