I currently have an HP Desktop the basic specs are: AMD Athlon - 3GHz 512 mb Nvidia GC 3 GB Memory It only cost about 400 - 500 dollars to purchase and upgrade. I don't do any gaming but I do HD video editing. I am looking at a general iMac with roughly about 3 GHz, 4GB RAM and it appears to be 256 MB card (either shared or discrete). So I am wondering if I am losing any performance by going to an iMac considering the it costs a bit more and the graphic card is somewhat questionable? Thanks in advance and I appreciate any feedback or comments.