There is also another more important difference. It’s the cooling system. Tyan paid due attention to proper cooling of the graphics chip as well as of memory chips and even of the onboard voltage regulator. You can see in the snapshots massive heatsinks installed on both sides of the card. Let’s dwell upon this cooling solution for a while.

In fact, RADEON 9700 PRO consumes 45W at most. It’s quite a lot, but ATI refused to use any big coolers, like the ones installed onto GeForce4 Ti4600 or GeForceFX. We have a small active cooler instead, which proves to be quite enough for the reference card to work stable at its regular frequencies and even to have some overclocking potential.

Graphics cards following the ATI’s reference design don’t have memory chips cooling. There are no heatsinks, although BGA-packaged DDR SDRAM working at 620MHz heats up considerably. All this suggests that RADEON 9700 PRO based cards don’t actually require such a big cooler as used in Tachyon G9700 PRO for stable work and overclocking.

The cooler in Tachyon G9700 Pro consists of two parts. One is installed on the front side of the PCB, the other – on the backside. That is, we have got a fully-fledged active cooler for the graphics chip and memory chips and a heatsink to cool down the memory chips and the core from the backside of the card. The cooler has nothing exceptional about itself. Its aluminum heatsink is made with the extrusion technology, so all the ribs are parallel and are of the same 8mm height. The fan is 50mm in diameter. It blows the air along the ribs, but as they are parallel, the airflow will spread unevenly through the heatsink. That’s why we may suppose the upper memory chips will be cooled less effectively than the ones installed in the right part of the card’s PCB.

When we took the front side of the cooler off the graphics card, we saw five thermal pads that lie in between the heatsink and the graphics chip with four DDR SDRAM chips. These are synthetic polymeric pads, and those of them that touch memory chips are rather thick: about 1.5mm.

The backside heatsink has the same shape as the front-face cooler. The ribs of this heatsink are about 1.5mm high and stand in parallel, too. This heatsink touches the front-face cooler in its upper part, but we can’t refer to the two heatsinks as to a single whole as they have very weak contact between each other.

The heatsink carries four polymeric heat-conducting pads, the same as the front-side cooler has. These pads press against the memory chips.

This heatsink also takes heat off the graphics chip. There is another heat-conducting pad glued at the back of the PCB right under the die. The heatsink touches it with the foot of a small cylindrical lug.

We won’t make guesses about the efficiency of such a cooling solution made up of two heatsinks. We will see it at work during overclocking.

Tyan Tachyon G9700 PRO has one more aluminum heatsink cooling power units of the card. Actually, it’s the first time we see a heatsink installed there. All other graphics cards we have tested usually use a regular heatspreader plate instead of the heatsink.

The heatsink is glued to two chips that are a part of the power circuitry of the card. It was rather loose-sitting and ready to break off, but this might have been a defect of our given card only.