The first thing you'll notice about the X2 is the size of the card. At 265mm in length it is as long as an 8800 GTX or 8800 Ultra and with its standard cooler attached it weighs a colossal 1.023 KGs, which is actually significantly heavier than either of the above nVidia cards.
The reason for the extra weight is mainly due to the extra metal used in the cooling mechanism which, unlike the coolers used on nVidia's high-end cards, includes a section of heatsink that covers most of the back as well as the front. Also, the front heatsink is considerably longer than anything we've seen before and it incorporates a lot of copper, which is heavier than more oft used aluminium.
There's actually a fair bit of science going on with the stock cooler on this card. According to ATI it has been developed with "enhanced weight management" in mind, which is a term I'm sure you're all familiar with - no?
Basically what this amounts to is the heatsink uses a combination of copper and aluminium to distribute the weight of the card so the extreme length of the card doesn't lead to it pulling itself out its PCI-E slot. Whatever it's called, it seems to work and the card sat secure and happy in our test bed. Of course, the big test will come from mounting it in a tower case, where the card is no longer resting on the motherboard but hanging from the PCI bracket and PCI-E slot. You'll have to make sure it's securely screwed in place or we can guarantee you'll end up with either a snapped PCI-E connector on your card or a PCI-E slot ripped from your motherboard.
Like most large graphics cards, the X2 uses a centrifugal fan to suck air from inside the case and blow it over the heatsinks and out the back of the card. As we would have expected, it performed very well, remaining reasonably quiet when under load and to all intents and purposes becoming silent when the card was idling.
One last note on the cooler, we've seen at least one card partner going a completely different route to the ATI stock cooler by removing the heatsink on the back and replacing the single exhaust fan with two fans that blow down onto the card. We've given this card a quick run through (expect a full review soon) and these changes don't seem to affect performance but they have made the card considerably lighter, which is no bad thing.