So we come to the cards that will actually be using the GF104 chip. Like the GTX 480, the new cards won't actually use the full potential of the chips they're based on. Instead, one of the SMs has been disabled. This is because the art of manufacturing these chips is a fine one and even the slightest defect can render a chip useless. As such, if Nvidia promised a full working chip, it would have problems producing them in enough numbers. By disabling the section of the chip that is defective, many more can still be used. This isn't a problem unique to Nvidia, but it is obviously still suffering more from it than AMD/ATI as that company hasn't had to resort to such measures.
There will also be two versions of the GTX 460, one with 1GB of RAM and one with 768MB. The latter also has a reduced memory sub-system with the amount of L2 cache dropping from 512KB to 384KB and the number of ROPs from 32 to 24. We shall be taking a look at this version of the card shortly.
Today, then, we're looking at the Zotac GeForce GTX 460 1GB, which uses a reference design and runs at standard clock speeds, unlike some cards on the market that come pre-overclocked. Nvidia hasn't stipulated a stock cooler for the GTX 460 and has instead left it up to board partners to choose their own setups. As such there are a number of different variations on offer.
The card we're looking at uses a radial fan sucking air in from the front of the card, blowing it across the heatsink and out the back of the card. Others use axial fans blowing straight down onto the card. Generally we prefer the approach Zotac has taken as these coolers exhaust the hot air straight out of your PC case. However, this particular design isn't the quietest we've encountered with it idling at 48dB (measured from 30cm away) and rising to 53dB under load.
In contrast the stock (i.e. Nvidia designed) cooler on the GTX 470 runs at 40dB/50dB, while ATI's competing cards also run at sub 40dB when idling. The Zotac card isn't loud enough to disturb you if you're just sitting working with some music on, say, but if you have your PC in your bedroom, it may be enough to keep you awake at night.
Otherwise, the Zotac design seems fine. It's 218mm long, which is plenty short enough to fit in most cases, and you get oodles of video outputs, with two DVI, an HDMI and a DisplayPort on offer – more than any other card we've seen from Nvidia.
One thing we didn't expect to see on a card that looks fairly small and unassuming is two six-pin PCI-E power connectors. The official TDP of the GTX 460 1GB is 160W, so it just creeps over the safe limit of using just one connector – it'll be interesting to see how much headroom this leaves for overclocking. Another interesting thing to note is the presence of only one SLI connector along the top edge, which means you can only run two of these together and not three.
In the box, along with the card, Zotac also bundles a copy of Prince of Persia: The Forgotten Sands, two twin-Molex to six-pin PCi-E connectors and a DVI to VGA adapter. Zotac also offers a competitive 5 year warranty on its cards. All told, we think it's quite a compelling package. All that's left to do know is see how the thing performs.