I was impressed with the quality of a VisionTek HD2600XT AGP card that I bought a couple years ago. It has a substantial heatsink on both sides of the card which seems to be better than what I've seen in photos of competing cards. The caps are also good. It uses a mixture of Japanese solid polymer caps and some Japanese brand liquid electrolytics.
It seemed that the heatsink might have also been meant to cool the Express->AGP bridge chip. It comes very close but doesn't quite touch it. Not sure if they meant it to make contact, but if they did then they failed to get the clearances right. This is disappointing, but no worse than competing cards which typically don't have a heatsink in that area at all.
The auxiliary power connector is a modern 6-pin, not the 4-pin molex that most competing HD2600XT AGP cards use. The 6-pin safely supports more current than a 4-pin molex. It comes with the cost of being less convenient for people with older power supplies and requiring them to include an adapter in the box. I like the fact that in spite of those marketing/cost concerns, they still made the choice to use the 6-pin.
Of course, that's just one model of card. I don't know if other VisionTek cards are this good, but this example impressed me.
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I had a bad experience with a Gigabyte HD4350 (bought new). I don't know whether the blame lies with Gigabyte or ATI. It was a factory overclocked card, which is something I'm a bit leery of. In games it seemed that there would always be a flickering surface *somewhere*. It was just a matter of looking around and finding it. Sometimes it would be something tiny. Other times it would be an entire wall. It was kind of like living in one of those Star Trek episodes where they look around and find glitches in the holodeck.
Playing around with drivers didn't fix it. I couldn't underclock the card to ATI standard clocks because this screwed up something with my dual monitor desktop (I don't remember the details). IIRC the underclock didn't resolve the issue in games anyway, but it was a long time ago so my memory is foggy. I just know that in the end I never found a good solution.
This issue might not have been indicative of other Gigabyte cards. But combined with my experience with 3 new Gigabyte motherboards around the same time (which all had different random problems), it led me to not trust Gigabyte anymore.
Baoran wrote:
The capacitors look like Sanyo and Nippon polymers, which are very reliable. However, the picture isn't quite detailed enough to be totally certain.
I don't know how the cooling compares to other X850XT cards, or how reliable their fans are.
Like capacitors, fans are another common failure point for graphics cards. I don't know any way to guess the fan quality other than by searching for anecdotes. You can't see what brand of fan graphics cards are using unless you are lucky enough to find pictures of somebody taking one apart. Now that Photobucket has died, half of the old teardown pictures on the internet are 404.