Shopping for a new computer is difficult enough with all the specifications these days, and it’s only made worse when you need something 100% compatible with Linux. This of course can be mostly avoided by going to a vendor that deals exclusively in Linux based PCs, but sometimes you may need more selection or a better price than these vendors have to offer.
The first thing you should look at is the manufacturer. Some manufacturers (Dell for example) have a history of being relatively Linux friendly whereas others do not. This is even more true for Linux desktops, which are much less common than Linux servers.
Next, look at the manufacturers of the parts inside the computer. The same rule applies here; NVidia for example is much more Linux friendly than ATI, so you probably (not always but usually) won’t want to go for a computer with an ATI video card.
Last but not least, once you’ve narrowed it down to specific manufacturer or a manageable number of PC models, try to find users who have had experiences with these models. Look up reviews on your distribution’s forum community, or a general purpose Linux hardware compatibility site like Linux HCL.
The process can be lengthly and tedious, but we all know it’ll be well worth it when you have your new Linux PC up and running smoothly!