Re: need upgrading help.
well, starting with the video card.
From what i can see, the 7600GT didnt need a 6-pin PCI-e power cable, BUT any good new GPU is going to need one. This would mean a new PSU most probably. PCI-e x16 slots are all for the most part the same, so no compatibility worries there. The CPU socket on the motherboard is AM2, the new AMD Socket for the athlon/Phenom II duals/quads and hex core models is AM3. You would only be able to upgrade your CPU to other AM2 CPUs. The motherboard doesnt have a manual or any recognition at all on the ASUS site, but from google images i gather that it has a fair few RAM slots. However, it will only take DDR2 (240-pin) DIMMs. It's hard to find out the maximum speed without a page of info on the mobo, but using the 333MHz as a guide, this is pretty slow RAM. You might be able to get up to 800MHz but it would be a gamble since we dont know for sure if it would work.
So, you're a little bit stuck for upgrades other than for the GPU, and it might require a PSU upgrade as well.
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