Back in February we looked at the Sapphire PC-AM2RD790 and posed the question: when is a Sapphire not a Sapphire? We revealed the startling answer was: "when it's a Sapphire PC-AM2RD790" as the board was a rebadged DFI and little to do with Sapphire at all.
Today's question is: what on earth could possibly be exciting about the Sapphire PI-AM2RS780G? On the face of it, not a lot, as this Micro-ATX design appears to offer very little. It looks considerably duller than the Abit AX78 that we reviewed a couple of weeks back. It supported the AM2+ socket with an AMD 770 + SB600 chipset combo and had a funky OTES passive cooling system, dual PCI Express slots, digital audio output and a great little flick switch to clear the CMOS - all useful and attractive features.
The Sapphire has none of those features, but what it does have is the new 780G chipset with Radeon HD 3200 integrated graphics. AMD's 780 platform comes in two variants that have a great deal in common: the 780V (for value) features the DirectX 10 HD 3100 graphics core with 40 Unified Shaders and support for dual displays, while the 780G uses the Radeon HD3200 graphics core. We've seen something similar with the AMD 690 chipset but 780 takes this to a new level, with the choice of VGA, DVI, HDMI and Display Port connections.
No doubt you're thinking about the prospect of a Home Theatre PC with the Sapphire ticking away at its heart, it's the primary appeal of the platform after all. In which case we might as well break the bad news now because the PI-AM2RS780G has VGA and DVI outputs but doesn't give you the choice of HDMI. This is a crying shame as the revised video processing in the graphics core will handle Blu-ray playback with a CPU load of less than 30 percent, making it ideal for an HTPC.
Still, this Sapphire board has some benefits as its based on the 780G spec with an HD 3200, which features a higher clock speed than the HD 3100 and the adds support for Hybrid Graphics. The idea behind this feature is incredibly simple. Until now any motherboard with an IGP would automatically disable the integrated graphics when you install AIB (Add In Board) graphics. The historical logic was impeccable as any graphics card was an improvement over any integrated graphics - until now.
The HD 3100/3200 core is very similar in specification to a Radeon HD 3450 graphics card; although the core speed is a little lower and it lacks dedicated local graphics memory. Even so there is the scope to use the 780G graphics core to assist the AIB by joining the two cores in CrossFire.
As it is early days with Hybrid Graphics you need to proceed carefully with the installation to allow the Catalyst drivers to sort things out. First you have to set the BIOS so you PC boots using the IGP. Generally you'd leave this feature on Auto and you can do that if you wish to use either the IGP or an AIB, but life isn't so simple with Hybrid Graphics and Sapphire doesn't help the cause as this feature is tucked away under ‘Miscellaneous Control'.
Start your PC, ensure the drivers are up to date with Catalyst 8.3, shut down your PC, plug in the graphics card and start it up again. All being well Windows Vista will use the drivers to automatically install the graphics card in addition to the 780G core and you can then open the Catalyst Control Centre to enable CrossFire.