Sidewinder: Every ATI card I've ever owned hasn't been worth the gold in the electronics compared to the competing level nVidia Card, and I've tried a couple dozen of them over the last 16 years. I've been involved in multiple betas, and releases and it's almsot always an ATI card with a glitch. To claim ortherwise shows a severe lack of actual experience with gaming and blind allegiance to a brand. Between my MX440 and my 8800GTX I tried 3 of the "nVidia Killer" cards by ATI and always went back to my MX440 for better performance, it was assinine (and no this isn't conjecture but actual monitored in game FPS numbers and playability levels).
Just because you personally have never had a problem doesn't mean that you are the majority, and while yes there are SOME games that offer nVidia cards a few isues, they are a minority comapred to the issues ATI has had since the birth of the 3D accelerator, I still miss my Voodoo 2 SLI rig.
Hell I was running a HD4850 in my media center PC... have had to replace the fan on it 8 times in 3 years, and it still got out performed by my GeFroce 8800GTX 256MB card, on the same board, processor and hard drive.
Have you even read my post before commenting? It's not just my experience, it's what I've observed as a whole from the gaming community via forums like this one. In any threads on graphical issues there are usually between 3-5 times more users using Nvidia cards than ATI/AMD ones, which exceeds the Nvidia vs ATI market share ratio the last time I checked. The fact that many of these titles were supposedly optimized for Nvidia cards does not help it one bit.
It's also seems somewhat hypocritical that you are accusing others of basing facts on their own experience (even though I've stated otherwise and gave you my source of info), and yet your first and largest paragraph reply talks about your good experience in using Nvidia cards. I certainly don't mind people sharing their opinions, but for a person like yourself who down the line went to pick faults with someone's experience, that's just weird, if not deliberate.
The HD4850, if you've done some reading from other's experience, does run a little hotter than comparable cards. My friend and myself who owns the card, however, had no issues with multiple failures as you did. If you had to replace your fan 8 times, you're either buying the wrong brand (remember, cards with the same number doesn't mean they are exactly the same), or more likely, your PC isn't properly ventilated - especially when used for a non-heavy duty role like a media centre PC. We do HD video rendering, 3D modelling/rendering, software development and of course gaming on ours, and had no issues. I also have a TV card running on it and 3 HDDs, so I don't think it generates any less heat than yours. Check your setup.
Can't comment on the 8800GTX, though from what I read its a pretty good card even when its old. Beating many of the lower and mid-end ATI cards and even some of the newer Nvidia ones. But performance does not equate to stability and I stand by my statements on how more Nvidia users seem to be having issues, until the real-life user accounts on forums changes of course. It should never be about brand loyalty or fanboy-rism; consumers should go for what works.