6800 series: always sold out - 6800GT had a bit of stock, but not loads, Ultra wa never in stock though.
7800 series: always sold out - Terrible stocking of the GTX, GT was popular though, so yeah, hardly any stock.
7900 series: always sold out - Same thing, GTX always sold out, even though it was bloody expesive, GT in plentiful stock, EXTREMELY popular.
8800 series: always sold out - I always saw the GTS in stock, although the 320MB was always being sold off. Ultra has limited stock still though.
8800GT: always sold out - What stock?!
X8x0 series: Very popular, but always plenty of stock - I only think the XT and XT PE ever had trouble with stock, but the X850 was more plentiful.
X1800 series: Ew. - And that's why it's still in stock... 6 months late, lower performance than Nvidia's showings, and expensive. Still good performance, and cos of the availability, it was the "alternative" card, IIRC.
X1900 series: Very popular, but always plenty of stock - In the UK, the XTX had some trouble at first, beng found, but the XT was the most popular anyhow. Cheaper, almost as quick, highly overclockable, and nearly always available.
HD 2900 series: Too much hype, but in the end...there were plenty of 2900's still on shelves - Still are, though yields are surprisingly high, so the GT and Pro are only limited editions, probably just to get rid of the less sable cores.
HD 3800 series: Flying off the shelves like freaking hotcakes. - Better stock than the 8800GT, that's damned right.
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