Radeon HD 2900 Pro Board Analysis
Besides sharing the same GPU, the Radeon HD 2900 Pro and 2900 XT share one other feature in common: theyíre both based on the exact same reference board design and cooling. In fact, if we peeled off the ďPowerColorĒ and ďHD 2900 ProĒ stickers on the top of our PowerColor Radeon HD 2900 Pro card, youíd be hard-pressed to spot any differences between the PowerColor card and our reference Radeon HD 2900 XT card AMD sent us several months ago. All of the core pieces of the 2900 XT board design carry over to the 2900 Pro 512MB, youíll even notice the 8-pin PCIe 2.0 power connector is used.
Because the basic board design of both cards is so similar, this makes it very easy for AMDís board partners to produce the 2900 Pro cards: all you have to do is recycle your existing components already used for the 2900 XT. This is important, because the Radeon HD 2900 Pro is a limited edition release (only PowerColor/TUL, Sapphire, HIS, and ITC will be selling 2900 Pro cards), in fact itís rumored that the board will reach end of life status at the end of October and production will at that point come to an end. With this in mind itís obviously not worth the time and expense for AMDís board partners to come up with a new board design and cooling for such a limited product. Instead itís more important to get it to shelves as quickly (and affordably) as possible, hence the use of the 2900 XTís board design and cooling.
Why release such a limited part now?
This is a question weíve received numerous times since the 2900 Pro was announced last month. The answer is simple: this is basically the equivalent of a clearance sale on R600 from AMD. This is essentially a way for AMD to clear some inventory of excess R600 chips before their upcoming RV670 GPU debuts later this year.
If you look at ATIís history youíll recall they did this two years ago with the X800 GT and X800 GTO where a mixture of excess R480/430/423/420 GPUs were released by ATIís board partners just months ahead of the release of the R520 GPU that was ultimately found in the Radeon X1800 XT. Weíre basically seeing a repeat of the same situation now with RV670ís introduction expected shortly.
RV670 is rumored to be based largely on R600, only itís built on TSMCís smaller 55-nm manufacturing process. All 320 stream processors will carry over intact and clock speeds are expected to be similar to the 2900 Pro Ė 600MHz core/900MHz memory Ė only it will utilize a narrower 256-bit memory interface. Leaked images of RV670 show a card with single-slot cooling and itís expected to support PCIe 2.0.
GDDR3 vs GDDR4
As we outlined in the table on the previous page, AMD will be offering 2900 Pro SKUs with GDDR3 and GDDR4 memory. The GDDR4 cards will ship with 1GB of memory, whereas the GDDR3 boards are limited to 512MB, which sells for $50 less. Personally we think most of the gamers in our audience should opt for the 512MB board, not only because itís cheaper, but also because we havenít seen any apps that take advantage of the additional 512MB of memory. Back in August we reviewed Diamondís 1GB Radeon HD 2900 XT card and found it performed largely identical to the 512MB 2900 XT card. Since then newer games have come out like BioShock and World In Conflict, but they donít seem to take advantage of the additional memory either.
On top of that, another reason why we prefer the 512MB card 2900 Pro over the 1GB variant is latency; up to this point ATI has used GDDR4 modules with higher latencies than GDD3, so itís possible that 2900 Pro 1GB cards may run slower than 512MB boards.
PowerColor bundle and Accessories
PowerColor includes all the basic hardware accessories youíll need to get your 2900 Pro card up and running. Inside the box youíll find two DVI adapters as well as the HDMI adapter youíll need to hook the card up to an HDTV. Remember that the R600 chip can carry audio over HDMI as well, so a passthrough cable isnít necessary. PowerColor also includes two power adapters, a component video cable, CrossFire cable, and a VIVO (video-in/video-out) cable. Software bundled with the card includes the driver CD, as well as a DVD-ROM with various programs from CyberLink, including PowerDirector, MediaShow, MusicMatch, PowerDVD, PowerProducer, Power2Go, and trial versions of PowerBackup and PowerDVD Copy.