AdrianII, just like Prole said, I need to remind you that any PC user should forget about Intel monopoly. The only reason Intel stands so strong with a market share around %80-85 (not latest ratios) is since they were in the market alone for tooooooo long. AMD processors can work out very well, and it's been a legacy that "AMDs overheat and burn". Intel's one newer CPU core had serious problems with overheating while AMD sustains its quality under performance/cost terms and never faced such problems recently.

Tip : Do not get stuck with the frequency of your CPU (that is Ghz), keep a close eye over L1, L2 caches as well. The only difference between a Celeron processor and a P4 processor was Celeron having no such caches (or very low ones) though both working at the same frequency. And that's why you would not prefer a Celeron for a gaming computer.

Gaming and photo editing will need more RAM, me thinks. 1GBs of RAM is enough, of course, but if there is any extra many I'd recommend it spending it on one or two more modules of RAM. (Consider buying 2* 512 RAM instead of buying a single 1GB RAM. So that you can benefit "Dual DDR" tech)

The ATI x600 video card did not convince me about its capabilities. For a new computer, I suggest looking at Nvidia 6600GT, 6800 (always keep off LE series) or the new Geforce 7 series. I'm not much into ATI video cards but I can easily agree on ATI 9800 Pro or XT video cards being very capable and powerful.

The x600 is not a crappy video card. But video card should have higher priority in case the configuration is changed.

Hope this helps

Once more again, the best way to build a powerful and less-costing machine is keeping off the branded systems and building your own brand with your own preferences