Merc, our RMA figures for video cards are very low. Like really low. I'd have to do a lot of trawling through the paperwork to put an exact number on it, but let me put it this way: every item that comes into the shop gets a coded stamp that tells us who we bought it from, on what date, and how long the warranty is. From this stamp, we can track down the invoice number and RMA the product if we need to. If we don't have the stamp (let's say the customer has removed it himself for some stupid reason), there is nothing we can do to get RMA service on it as we can't trace the part. No stamp, no warranty.
For parts that are really, really cheap (e.g., $6 speakers, network cables, 10/100 NICs) we don't bother stamping them, as it's not worth sending them off for warranty replacement anyway. Nor do we do it with moderately cheap parts that almost never fail inside the warranty period (e.g., Logitech mice, Panasonic floppy drives) as the time wasted stamping stuff that isn't going to fail anyway is just that: wasted time. Finally, we don't do it with stuff that is particularly difficult to stamp (notably cases, where you would have to buggerise about opening, unscrewing, stamping, and re-sealing). The cases we use only have a PSU fail once in a blue moon anyway. So when does fail, we just throw it away and don't worry about it.
Anyway, a few months ago, Kristi and I discussed stamping video cards. Was it even worth opening each box to put a warranty label on the card? I said "no", she said "yes", but neither of us held our view very strongly. In the end, we decided to keep on stamping them, mainly because (as Kristi pointed out) it's a job you can do in low-priority time, such as when you are stuck on the phone listening to some yammerhead waffle on endlessly.
The point is, we only just barely even bother to put warranty stickers on our video cards these days (except the high-end ones, of course - they are too expensive to take chances with). The return rate is so low that it's a line-ball decision as to whether it's worth 30 seconds a card to give ourselves warranty cover.
We use Leadtek cards almost exclusively. Sometimes Albatron, but the Leadteks are clearly better. Most of them are fanless. All of them - yes, 100.000%, are Nvidia-based.
We see all sorts come into the workshop, of course: all brands, all chipsets. But we haven't sold a non-Nvidia card new since .... hmmmm .... well, let me list the last non-Nvidia cards I can remember: Voodoo III, IV and V; 8MB S3 AGP 2X; Matrox G450 32MB; and some appallingly bad ATI-based 8MB AGP cards that leave a bad taste in our mouths to this day. Those were all a long time ago. No, wait: a supplier sent us one for nothing a while back: buy ten motherboards, get a video card free, or some such. I thought about using it, then took it to my competitor a few doors down the road and swapped him for a CD burner.
Now I personally wouldn't touch an ATI video card with a 10 foot pole. Practically every time we see one, it's trouble. I hate the bloody things. I do, however, have enough brains to realise that other people have had good success with them, and respect that. Hell, I could probably learn how to make the bastards work myself, if I had any reason to do so. But why should I? Nvidia cards are utterly fuss-free, reasonably priced, and (at least so far as our Leadteks go) utterly reliable.
Rule 1: never change things that work for you. Or is that Rule 3?