TTBOMK, the only companies that truly *make* (at least some of their) cards (meaning they are the ones who physically put the traces, components, chips, etc onto the PCB) are:
And then I'm sure there's various card makers that sell to others but don't market cards with their own name, like Foxconn.
The rest of the companies out there (again, TTBOMK) just sell re-branded cards that were 'made' by others, sometimes changing the cooler and clocks and such but not really 'making' them in the literal sense. These include:
and the venerable BFG (RIP).
The remaining companies I'm unsure of in terms of whether they actually 'make' anything: PNY (think not), Sparkle (think they might), Zotac (think not), and Galaxy (think they might).
Again, this is strictly to the best of my knowledge, and if someone knows differently, I'd be delighted if they shared their insights on the subject.
Personally I like MSI, GB, and Asus because I always end up selling my cards long before they die, so the non-serial based warranty works better for me.
Edited by brettjv - 5/18/11 at 1:54pm