Hi, I know there is no official way to do this as iMac's are not upgradeable etc but as an experienced computer techie I am 100% comfortable with disassembly for hard drive replacement, logic board replacement etc. So, with that out of the way, can anyone tell me if it is possible to upgrade the GPU on a 24" 2.4GHz August 2007 iMac from the 2600 to the Nvidia 8800GS. If so, is this a GPU swap alone or is it a complete logic board swap which is required? Any other parts required? Any issues with the machine getting confused about which hardware it's running when doing software updates etc.? I am hoping to be able to make use of the OpenCL stuff in Snow Leopard so I am evaluating my options. If the GPU could be swapped then I would look for a 2nd hand logic board or GPU board and upgrade it myself but I'd like to know if anyone has done this before first. Many thanks, Craig.