There may be little support past a few years and certainly none for free today. Today all support outside of warranty is a pay for it deal. I'm finding folk calling this not being nice but employees cost money, phone lines and more.
Back to your search. There are far too many desktops out there for that price.
Well, I currently have a broken COMPAQ Presario from '04 that is broken, and HP is making very little progress in helping me, so if worse comes to worse, I was thinking of what computer I should get.
I am on a budget of about $650.
I would like a good built in GFX card, that would be able to play games like StarCraft II, Team Fortress 2, and Mirror's Edge well.
I'd also like it to be able to run Phot editing software well. (GIMP, PSE7, etc)
I'll post more detail, but I think thats about it.
Oh. I'm Canadian, so keep that in mind for Companies and Prices.