Announcing RS690 and Kaleidoscope IGP; Expanding the ATI Core Logic Sector

Our first report on the RS/C400 and RS/X480 came back in April, and things changed a little with our July update. We now have the latest information on ATI's upcoming chipsets, and it helps to clear up a few things. Let's start with the Intel chipsets.

First, we have the RC/RS400. The RS400 is the high-end dual-channel version, while the RC400 is a single-channel solution. Performance of an integrated graphics solution will suffer on the single-channel solution, of course, but for most businesses it really does not matter. Remember that the next version of Windows, codenamed Longhorn, will require DX9 graphics support, so these ATI solutions will meet this requirement. The RV370 core comes from the X600 chip, which is really just a PCI Express version of the 9600 chip. That may not sound like much when compared with the latest X800 XT graphics cards, but when compared against competing integrated graphics that offer lackluster performance at best, it is not that bad. Radeon 9600 Pro cards are still capable of running all current games, although they may have to drop to lower detail settings to maintain decent performance in the latest titles. The RS400 IGP is said to be almost twice as fast as the 915G IGP, and it has the same drivers as ATI's desktop cards.

Something else that ATI has added on the high-end RS400 is support for component video out. Composite video combines all the signals onto one cable, while S-Video separates the data into two channels: one for black and white information and one for color. Component video takes this one step further by separating the color channel into Pr and Pb cables. The end result is that component video provides a higher quality signal than composite video and somewhat better quality than S-Video. Especially for HDTV connections, component output is desirable. It is still an analog connection, but it is a good analog connection.

The RC410 is basically a process shrink of the RC400 to 110 nm, which means it will be cheaper to produce and should generate less heat. Whether the performance will vary is not yet known. If you look at the past roadmaps from ATI, you will also notice that information on any non-UMA chipsets has disappeared. Looking to the future, we have the RC/RS600 chipsets, which we know little about other than that they will include a future graphics core and a display and video technology called "Kaleidoscope."

Other features on the RC/RS4x0 chipsets remain unchanged. They will all support up to 20 PCIe lanes and DDR/DDR2 memory. Whether they will include DDR2-667 support is not yet known, but it is expected. On the RC400, the PCIe support will be limited to one X16 PCIe graphics connection combined with any PCIe combination totaling X4 - i.e. four X1 connections, two X2 connections, one X2 and two X2 connections, or one X4 connection. On the RS400, the X16 graphics connection allows for more flexibility and could be split into two X8 connections, providing support for multiple graphics card configurations.

Moving on to the AMD side of things, we see a similar picture.

The RS/RX480 chipsets are identical in features, with the RX being a discrete graphics solution while the RS includes the RV370 core. ATI's AMD chipsets lag behind their Intel counterparts slightly, as the component video out support will not arrive until the RS482 chipset. Again, we see the "Kaleidoscope" display and video technology with a new graphics core with the RS/RX690 chipsets in the future.

The RS/RX480 chipsets support the HyperTransport protocol and their bus support is configurable, so they can be used with any of the AMD Athlon 64/Opteron sockets. As the memory controller for AMD processors is integrated into the CPU, the memory support is determined by the CPU and not the chipset. Integrated graphics are one item that can potentially use the additional bandwidth that DDR2 offers, but whether that will actually affect performance remains to be seen.

While we do not know for sure what "Kaleidoscope" is, ATI's comments about multiple VPU support may indicate that it has something to do with that technology. As for the new graphics core that comes with it, we know little. However, looking at the history of integrated graphics parts, we can see that they have typically lagged behind state-of-the-art desktop parts by 12 to 18 months. With a launch date of Q1 '06 and with the RV370 going into the current IGP parts, the likely candidate for the 6x0 parts would be some variant of the X700. We could hope for something more, like the X800 core, but with a transistor count of around 160 million that does not seem likely.

The last part of the ATI roadmap covers their South Bridges.

Early on, we had heard that the SB400 chipset would support both the high-end Azalia 8-channel audio and the older AC '97 audio. Later, this was changed to only AC '97 audio. The reason for this is now clear: we have two South Bridges coming from ATI, with the SB400 supporting the older AC '97 standard and the SB450 adding Azalia support. This actually makes a lot of sense, as adding high-end audio support for solutions that are likely to end up in businesses is not necessary. Motherboards targeting a lower price point can save a bit on costs and stick with SB400, while motherboards targeting the performance/enthusiast sector can opt for SB450. As far as SB600 goes, we have little information other than a name and a release date.

ATI still remains poised to deliver some of the first PCIe chipsets for the Athlon 64 platforms. With the push for native PCI Express graphics cards, the first company to offer such chips stands to gain some early sales. On the Intel side of things, ATI may also have something to offer in the way of overclocking support. Intel's current 915/925 chipsets have made it somewhat more difficult for enthusiast motherboards to overclock, and while ASUS and others have largely overcome the limitation, the same cannot be said for all 915/925 motherboards. There is no mention of such a limitation on ATI's parts, so we might still see support for DDR2-667 before Intel. We will certainly be investigating this when we review motherboards using these ATI chipsets.