I'm no Dell lover by any stretch of the imagination, but shouldn't at least some of the blame lie with the company who actually manufactured the motherboards in the first place?
I know a lot of these Dell machines use modified-Intel boards, and I've seen plenty of non-Dell built machines with blown capacitors. Intel 815, 845, 865, and 915-based boards all seem to share the same problem over time. I've yet to see any 945-based (or beyond) boards with failing capacitors, but time will tell I suppose.