New user here. My mum recently broke her imac, it's the 24 inch aluminium one from 2008/2007 I'm pretty sure. She sent it in to the Mac store to get it repaired but they couldn't fix it, so they sent the computer back to us with the hdd outside of the case. I opened up the computer and put the hdd back in, the computer was still freezing on the booting apple spinning wheel symbol. So i tried a few things like resetting the PRAM etc etc then i swapped the ram slots and tried again. That didn't work so i tried booting from the mac os x disc, that still didn't work. I then proceeded to insert a Windows 7 Ultimate 32x disc. Success, the computer successfully booted from the WINDOWS install disc and within 20 minutes i had windows 7 running on the imac. The imac has an nvidia 8800 GPU and the windows OS wasn't recognising the driver software for it. So everything such as movies, explorer windows and games were extremely choppy. I researched it and i found out that people who installed windows via bootcamp or as a single OS option oin the same model imac i have, have the exact graphics card issues, even inserting the Mac OS Snow Leopard OS disk and installing the bootcamp software didn't help fix my problem. So then i turned off the computer in a fiery rage. Around 10 minutes later, i switched the imac back on, not remembering that i left the Snow Leopard disc inside the computer's disc drive. Strangely enough it successfully booted from the SL cd and i was able to successfully wipe the windows OS and install Snow Leopard onto the computer. The next day i decided to install boot camp with windows 7 to see if the GPU problem had fixed itself if running in boot camp mode instead of using Windows as the single OS. The problem had not fixed itself. So I turned off the iMac and tried to boot into Snow Leopard so i could wipe the boot camp partition. For some reason i couldn't boot into Snow Leopard. I researched and tried many different ways to find boot problems, but none of them would work. I could not boot into Snow Leopard. I then proceeded to boot from the windows 7 install disc and completely wipe the hdd into a fresh start. I then tried to boot into Snow Leopard from the installation disc. It did not work. I then decided to take more drastic measures and inserted a different hdd into the computer via the SATA connection. Then i tried to boot from the Snow Leopard disc. Very strangely, the computer did not boot from it. It did the same thing as i did with the other hdd, freezes during the boot spinning wheel with the apple logo above it and shows the multi language grey screen that says "You need to restart your computer hold down the power button until it turns off then press the power button again." This is very strange so im sure that its not an hdd error because the Mac OS Leopard Installation cd didn't boot properly even with the new hdd i put in there. I have tried everything i can, this is a last resort. Help will be greatly appreciated.