AMD's next major product line update could be called the ATI Radeon HD-series. Wired News have posted a rumour that the flagship will be called the Radeon HD 2900 XT.

Boot Daily have already posted the RRP for the R6xx-series, while HardOCP grabbed some photos of what appears to be an OEM version of the R600 with a massive HSF that would be completely inappropriate in the retail market.

Benchmarks have also been posted which show the R600 outperforming the NVIDIA GeForce 8800 GTX, which is no surprise, but they don't seem to be available any more. It's quite likely that NVIDIA will release the GeForce 8800 Ultra around the time the R600 comes to market, much like the GeForce 7800 GTX 512 at ATI's X1800-series launch.

It'll be no surprise when AMD, arriving fashionably late as always, confidently takes the graphics performance crown with the R600.

DailyTech have posted some preliminary benchmarks of the Radeon HD 2900 XT. The best part of the preview is the pictures, depicting a more sensible cooler.

Architectural details are getting beyond the mortal man. The 512-bit memory interface 1650 MHz translates into about 103 GB/s, but it's now clear that AMD's definition of a "stream processor" isn't the same as NVIDIA's, or else the 320 steam processors of the R600 would outperform the G80's 192 by a significant margin.

If AMD do wrest the blue ribbon from NVIDIA, it's hardly a victory; sending your army to meet an invading force half a year later isn't exactly in SunTzu's Art of War. NVIDIA is bound to pull a "GeForce 7800 GTX 512" tactic in a trice, and these margins don't yet seem high enough to weather it.

HardOCP has written up a pretty scathing review of the Radeon HD 2900 XT, which does seem to plainly show that AMD's giant slayer is no King David.

The R600 surrenders to the cheaply GeForce 8800 GTS at every test, and dare not even cast an eye at the GeForce 8800 GTX. Brent Justice draws comparisons between AMD's flagship graphics card and the old GeForce FX 5800 Ultra (which failed to impress at the launch), and I concur.

Although from a technical standpoint, the R600 could be superior to the G80, but clearly it is not. Possible reasons include:

• AMD states the Radeon HD 2900 XT has 320 stream processors, however, this is really 64 units of 5 processors, and only one of the 5 is capable of certain types of operations. By comparison, the GeForce 8800 GTS is advertised as having 96 stream processors (which equals 192 in AMD's language), but the configuration of the R600 means the scheduler component needs to keep the pipelines packed to achieve real-world performance. The GeForce FX had a similar Achilles heel as well, as it was advertised as an 8 pipeline architecture just as the competing Radeon 9700 Pro; it was later revealed that it could only output 4 pixels per clock with a colour operation (this is required for you to actually see the pixel).
• The 64x5 stream processors are clocked at the same frequency as the rest of the core, where as the GeForce 8800 GTS' fewer 96x2 stream processors are clocked over two times faster.
• The R600's memory interface might seem a lot wider at 512-bit vs the GeForce 8800 GTS' 320-bit, but it really needs that bandwidth to fill its hungry maw. It's quite conceivable that it could benefit from a higher clock speed. NVIDIA made the same error with the GeForce FX 5800 Ultra by jumping on board with DDR2 memory before they were able to achieve a 128-bit memory interface, starving their GPU.
• Where's the XTX? It wouldn't be a surprise to find that AMD has problems scaling up the R600 - the 742 MHz Core clock (instead of say, 750 MHz) seems to hint at this. It wouldn't be a surprise to find out AMD has rushed to push something into the market to compete against NVIDIA before they were really ready. A significantly faster and more competitive Radeon HD 2800 XTX variant clocked at 800+ MHz may follow soon. Maybe they will overcome some of the power leakage problems and multiply their stream processor count (just like the Radeon X1800 XTX to X1900 XTX refresh). Don't hold your breath though.

Interestingly, the Radeon HD-series graphics controllers also have basic integrated sound controllers. These seem to be pretty low resolution (16-bit), software accelerated affairs that are basically there to support HDMI. Despite the marketing slide show, this is no replacement for your on-board sound controller let alone that nice new X-Fi. There are also a bunch of new and useless anti-aliasing modes that just makes things look worse.

On a positive note, the mid-end Radeon HD 2600 and Radeon HS 2400 cards, due out Quarter 3, could be worth more than the cardboard box they come in.

X-bit labs have written up a very technical analysis of the R600 architecture and Radeon HD 2900 XT performance.

Arriving at the same conclusions at HardOCP, X-bit labs have questioned the tardiness and mediocrity of AMD's launch product by highlighting the odd design flaws and bottlenecks revealed in analysis.

The question lingers; can AMD put their house in order with the launch of the Radeon HD 2900 XTX?

The R600 appears to respond fairly well to overclocking, both the sensible kind and the excessive kind.

In their mini-article on the launch of the Radeon HD-series, Ars Technica briefly discuss the new software layer that is required for the new architecture to function. This is an interesting clue to why performance is slightly less than jaw-dropping at the moment.