AMD's 890GX chipset is designed as a top-to-bottom solution for all socket AM3 CPUs, including the 140W six-core Phenom II X6 CPU. AMDs 890GX chipset is built on the 55nm process (~200M transistors) and combines the best features of AMD's 790GX and 785G chipsets with native SATA 6Gb/s via the AMD SB850 southbridge, an integrated Radeon HD 4290 graphics engine and Gigabit Ethernet MAC. A-Link Express III bandwidth between the two chipsets now sits at 2GB/s, though the connection to the processor remains 5.2GT/s HyperTransport 3.0.

Several other variants of AMD's 8-series chipsets also exist, including the AMD 890FX/SB850, 870/SB850, and 880G.

ATI Radeon HD 4290 Integrated Graphics Processor

The AMD 890GX chipset is suitable for both integrated graphics and those that want to run single or dual add-in (discrete) graphics cards. The AMD 890GX chipset has x16 lanes of PCI Express 2.0 bandwidth, which can also be split into dual x8/x8 lanes, with support for ATI CrossFireX graphics.

If you're not using discrete graphics, the AMD 890GX chipset will switch to the integrated Radeon HD 4290 graphics processor. This IGP is very similar to the Radeon HD 4200 IGP found on AMD's 785G chipset. Both IGPs have 40 shader processors, support for DirectX 10.1 and Shader Model 4.1, ATI Steam, Unified Video Decoder 2 (MPEG2, VC-1, and H.264 formats) and dual-display output over DVI/HDMI/DisplayPort and VGA, as well support for an optional cache of integrated Sideport memory, which will give a small boost to graphics performance.

While the previous Radeon HD 4200 IGP had a core clock speed of 500MHz, the AMD 890GX chipset's Radeon HD 4290 graphics has had its core clock speed turned up to 700MHz.

700MHz AMD 890GX chipset and 128MB of DDR3-1333 SidePort onboard memory.

If you prefer to use both integrated and discrete graphics together, there's AMD Dual Graphics. This technology is similar to the ATI Hybrid CrossFire graphics technology found on last generation's AMD motherboards. Hybrid Crossfire graphics let a chipset like AMD 780G and its RV610 IGP work with a discrete graphics card based on the same architecture, like the Radeon HD 3470. The AMD 780G chipset and Radeon HD 3470 combination would have some additional graphics muscle for gaming.

The problem with Hybrid Crossfire is that you were limited to matching up an IGP (designed to be economical, not for enthusiast gaming) with a videocard limited to the same speed as the IGP. This meant you had two relatively slow GPUs working together: definitely better than just the single IGP, but still not nearly good enough for 3D gaming.

AMD's Dual Graphics technology is meant to fix this by allowing you to pair the AMD 890GX's Radeon HD 4290 IGP with discrete videocards that have faster-clocked Radeon 5-series GPUs. When pairing an AMD 890GX motherboard with a Radeon HD 5450 graphics card, scores in DirectX 10 games saw a ~25% improvement in Dual Graphics mode.

Integrated Graphics Chipset Comparison AMD 780G AMD 785G AMD 790GX AMD 890GX Intel H55 CPU Socket AM2 Socket AM2/ Socket AM3 Socket AM2/Socket AM3 Socket AM3 Socket 1156 Memory 1066MHz DDR2 1066Mhz DDR2/ 1333MHz DDR3 1066Mhz DDR2/ 1333MHz DDR3 1333MHz DDR3 1333MHz DDR3 Graphics Expansion 1x16 PCI Express 2.0 1x16 PCI Express 2.0 1x16 PCI Express 2.0 / 2x8 PCI Express 2.0 1x16 PCI Express 2.0, 2x8 PCI Express 2.0 1x16 PCI Express 2.0 Peripheral Expansion 6x1 PCI Express 2.0 6x1 PCI Express 2.0 6x1 PCI Express 2.0 6x1 PCI Express 2.0, 2x1 PCI Express 2.0 on SB850 6x1 PCI Express 2.0 IGP Radeon HD 3200/RV610 Radeon HD 4200/RV620 Radeon HD 3300/RV610 Radeon HD 4290/RV620 Intel HD Graphics Shader Processors/MHz 40/500Mhz 40/500MHz 40/700MHz 40/700MHz 12/Varies by CPU DirectX Support DX10 DX10.1 DX10 DX10.1 DX10 Display DVI/HDMI/DP/VGA DVI/HDMI/DP/VGA DVI/HDMI/DP/VGA DVI/HDMI/DP/VGA DVI/HDMI/DP/VGA Southbridge SB700 SB7X0 SB750 SB850 Intel PCH Storage 6xSATA 3Gb/s 6xSATA 3Gb/s 6xSATA 3Gb/s 6xSATA 6Gb/s 6xSATA 3Gb/s USB 12x USB 2.0, 2x USB 1.0 12x USB 2.0 12x USB 2.0 14x USB 2.0, 2x USB 3.0 12x USB 2.0

Keep in mind though that AMD's Dual Graphics is still a work in progress, so support right now is limited to literally just the Radeon HD 5450 graphics card and its derivatives. Having AMD Dual Graphics enabled could be enough to push value oriented videocards into decent gaming platforms, or not. PCSTATS has not had the opportunity to test it first hand, we'll be following closely as developments occur.

AMD 890GX Northbridge

AMD has dedicated two of the AMD 890GX northbridge's PCI Express 2.0 lanes to a discrete NEC USB 3.0 controller, which itself powers two USB 3.0 ports. This has been done with other chipsets before, but with a fair amount of bandwidth-related compromises. Thankfully the AMD 890GX chipset has a fair amount of PCI Express 2.0 bandwidth to spread around, with x16 lanes dedicated to graphics, x6 lanes for expansion slots, and x2 lanes that are dedicated to USB 3.0 support (the SB850 also gets an extra pair of PCI Express 2.0 x1 lanes).