Review: R600XT finally revealed, a bit bitter

 The R600 chip is probably the most delayed chip in the history of ATI. It was supposed to show its face in October / November time but too many things went wrong.

The biggest problem of all was that the G80 was far better than anyone could have expected and Nvidia had a secret weapon, Shaders clocked twice as fast of the GPU speed.

R600 was a nice concept with 320 stream processors or Shader units divided in four blocks and 512 Mbit memory interface. Unfortunately this 700 million transistor chip was way to hot and the performance was not that great.



ATI was ready with its R600 generation in early March, but the performance was so bad that the company decided to postpone the launch till it gets a better driver. Well, they could not push it any further and ATI decided to launch the Radeon HD 2900XT, a cheaper high end card, and to cover the R600 flaws with a Half life 2 episode two voucher.

We had a chance to take a look at two cards, an ATI reference Radeon HD 2900XT and Power Color's Radeon HD 2900XT. As both cards were the same we decided to post the Power Color stuff only as it is based on the same reference design.



The card is clocked at 742/1650 MHz and these are the final clocks of the reference design cards. You can read more about the cooler here, but the story is simple. The card ends up very hot. My biggest problem with the cooler is that it tends to be quite noisy in 3D. In 2D mode the card works at 507 MHz core and it doesn't make much noise. 

Well, we wont pay much attention to the temperature of the card as the high end cards can get hot and even the 8800 GTX card ends up close to 80 Celsius if not more on the power components. The r600XT GPU heats up, up to acceptable 71 Celsius and it works stable.

The card comes with a voucher the same as we pictured a few days ago here.

 


AMD's own user guide suggests a 750W PSU and you can read it here but we tested and figured out that a single Radeon HD 2900XT works with a quality 500W as well. However it won't work with every 500W PSU, especially not with the cheap ones.



We won't go much into the architecture, as we wrote about it before but it is important to mention that ATI chip has 64 Shader units and they can deal with Vec5 scalar functions. ATI and a few developers claim that R600 has a much better geometry Shader than Nvidia but this is a DirectX 10 feature only and there are no any DirectX 10 games to put this claim to the test.

One other interesting thing is the DVI to HDMI dongle that should be able to take care of Audio but we didn’t had a chance to play with this much.



ATI has a few drives but the launch one is called 8.364, however we also learned that 8.374a and b were available to a few of reviewers. There should be a 8.378 that can improve the performance for additional five percent but this is yet to be seen.





The card has two PCIe power connectors one 4x2 pin for overdrive overclocking while the second one is the standard 3x2 pins. The card will work with two 3x2 pin connectors, but the driver wont recognize the overdrive overclocking option.



Finally the card has an internal Crossfire connector and it looks identical to the ones we saw on RV570 based Radeon X1950 PRO cards.

The package includes two DVI dongles, DVI to HDMI dongle, HDTV cable and Avivo analogue cables.



Let's not forget the Crossfire internal connector.  The package also includes the Voucher for Half Life 2 episode 2, team fortress 2 and portal games. You can also play Day of Defeat source game when you buy this card and unfortunately this is the only game that is actually out.

 


Test:

We used our usual test setup and compared the card with 8800 GTX and GTS 640 MB cards as these are the real competitors of the Radeon HD 2900XTX. In some scores we used an overclocked EVGA AC3 8800GTX 652/2000 MHz, so the card that should be very close to Geforce 8800 Ultra speeds.

We will focus on the scores of Radeon HD 2900XT versus Geforce 8800 GTS 640, but we will comment the other scores as well.

To make one thing clear at the beginning Radeon HD 2900XT almost never wins over Geforce 8800 GTX, not to mention the overclocked 8800 GTX. It is not in the same legue but to be fair it is a bit cheaper than these cards.

We used:

Intel Core 2 Duo 6800 Extreme edition
Nforce 680i EVGA board
Corsair Dominator TWIN2X1024-8500 at 5-5-5-15 at 1066 MHz
Seagate Barracuda 7200.9 400GB SATA NCQ hard drive
Akasa EVO AK 922 Blue Athlon 64/X2/FX cooler and Intel CPU's
Silverstone DA750W modular PSU