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AMD's 780G integrated graphics chipset

AMD's 780G integrated graphics chipset

Manufacturer: AMD

AMD’s 690G was its first chipset of the joint AMD-ATI venture – between this and its SB600 south bridge it made for an excellent and inexpensive combination that has retained its very strong position in the market, even until recently – we recommended this chipset on two MSI motherboards in the last year.

While the 690G featured a rebranded X700 graphics core with Shader Model 2.0b (DirectX 9.0) support, that was considerably behind the late X1000 range which featured full SM 3.0 features, AMD has gone to huge lengths to update its 780G to increase its performance across the board. In effect, it has jumped two generations.

The chipset now sports the Radeon HD 3200 nomenclature and features a unified Direct X 10 architecture with Shader Model 4.0 support. It even includes the complete Unified Video Decoding (UVD) engine for video offloading of MPEG-2, H.264 and VC-1 all the way up to full-HD 1080p resolution. The option of HDMI, DVI or DisplayPort is available, and all come with native HDCP support, but only one can be used at a time in addition to the VGA output for dual display.

In line with the latest Radeon HD 3000 series discrete graphics cards, the chipset is also built on a 55nm CMOS process, down from the 80nm the 690G used – this helps to reduce its power use from 1.4W to 0.95W—even despite the massive increase in transistor count from 72M to 205M. Translated, this means a 285 percent transistor count increase for 47 percent less power!

AMD's 780G integrated graphics chipset AMD's 780G integrated graphics chipset

As you’d expect, both HyperTransport 3.0 and PCI-Express 2.0 are now natively supported – there’s a single PCI-Express x16 lane in addition to the IGP, so a discrete graphics card can still be used. We did confirm that splitting the single PCI-Express 2.0 x16 lane into two x8s for CrossFire will work, however, it depends on the cost given the fact there are also readily available, inexpensive alternatives like the AMD 770X and 790X.

What AMD still includes the option of is a local frame buffer (LFB) – a lot of its quoted performance numbers are based on using this. This feature has been around for a while: when I reviewed an EQS RS400/SB400 motherboard way back in 2005, it featured a space for a BGA memory chip even back then. Again however, we don’t expect many manufacturers to use it even despite the improved performance potential it offers.

AMD's 780G integrated graphics chipset AMD's 780G integrated graphics chipset

This is because of the extra cost and the fact it’s an optional feature will again mean it is left out from virtually every motherboard in a very cost conscious market. Motherboard makers will likely concentrate on their own unique features to add value, because they have already pushed significant marketing budget behind them.

We asked AMD whether it expected a greater uptake this time around and it replied that the LFB was mostly used by OEMs and ODMs. This is because the cost of use is far lower because they can often negotiate a low purchase price for buying in bulk. End user motherboards require additional cost of bundle, package and marketing meaning that more varied features like eSATA and HDMI are more important than the LFB.