I wouldn't say no advantages. As much I dislike quite a few things about Windows 8 it starts absurdly faster than windows 7 and is aesthetically prettier. No question the tablet style start menu is a pain but I'm used to it now and know where everything is. So, actually, I think if I was to format I'd go back to windows 8 not 7.Honestly, with a desktop, I think a clean install back to Windows 7 would probably be ideal. You're not really getting any advantages to using Windows 8 on a desktop since the interface is more tuned to a touch interface. You wouldn't really lose anything by keeping on Windows 7.
Besides even if I do that there is a decent chance that my graphics card is just done. So it's not worth going through all the headaches of backing stuff up and formatting when even that isn't a guaranteed fix.
My Graphics Card was about 3 years old and not particularly high end even then so it was getting to be time for an upgrade anyway. Worst case scenerio, I'm forced to format anyway but this time with a nicer graphics card.