In the case of the Gigabyte GA-A75-UD4H motherboard
PCSTATS is testing in this review, AMD's Fusion platform consists of the AMD A75
chipset and socket FM1, AMD A8-3850 FPU processor. This 'Fusion'
platform is both an upgrade from previous IGP chipsets such as the AMD 890GX and
a complete departure from that era. The reason for that departure is
the AMD A75 core logic largely fulfills
the role of 'southbridge chipset' now.
FCH (Fusion Controller Hub)
The AMD Fusion CPU
architecture differs from previous AMD Athlon and Phenom II processors in that
it integrates not only the memory controller onto the CPU die, but also the
functions of the northbridge chipset and integrated graphics processor.
Consequently, the transistor count for the AMD Fusion A8-3850 CPU has ballooned
to nearly 1 Billion transistors. Despite the roughly 300 Million increase to
transistor count, AMD was able to keep the outward size and shape of its CPU
processor package identical to previous generation CPUs. It did this by
implementing a 32nm die shrink.
The AMD A75 'Fusion Controller Hub' chipset
supports six SATA III 6GB/s devices (with RAID 0,1,10), FIS-based switching,
four PCI Express 2.0 x1 lanes, three 32-bit PCI slots, four USB 3.0 & ten
USB 2.0 ports, and HD audio. The remaining platform features are allocated to
the processor. The CPU handles eighteen PCI Express lanes, a dual channel DDR3
memory controller, various video outputs and the integrated graphics core
(dependent on the specific CPU model).
The AMD A8-series APU has a somewhat higher powered
IGP than the AMD A6-series FPU, as you'd expect.
|AMD A75 Chipset
(*with A8-3850 APU)
|Bus Interface / Speed
||2600MHz HT 3.0|
|Memory Support (dual channel)
|Maximum Memory Capacity
AMD Radeon HD 6550D*
|Radeon HD 4290|
|Integrated Graphics Video Ports
||400 Shaders / 600MHz*
|PCI Express 2.0 Lanes
||4 + 20*
|SATA 6Gb/s | SATA 3Gb/s
||6 / 0
||6 / 0 |
||0, 1, 10
||0, 1, 10|
|USB 3.0 Ports
|USB 2.0 Ports
AMD Fusion A8-3850
processors (or FPU as AMD calls it) are equipped with a Radeon HD 6550D graphics
core. The Radeon HD 6550D IGP supports DirectX 11, DirectCompute, Blu-Ray 3D,
UVD3 and OpenCL. Video outputs will depend on the particular motherboard, but
the technology can support HDMI 1.4a, DisplayPort 1.1a, DVI-D and Analog VGA
When dual link is enabled on the DVI-D port, the
IGP can handle monitor resolutions of 2560x1600. Ditto for DisplayPort. HDMI
connected displays can be set to a resolution of 1920x1200. AMD Dual Graphics
enables the onboard graphics to be paired with a Radeon HD 6000-class discreet
graphics card in a hybrid CrossfireX arrangement. Tied to AMD Fusion A8 3850 processor, the Radeon HD 6550D graphics
core operates at 600MHz and features 400 Radeon Cores (shaders). Peak GPU
Compute is 480 GFLOPS while 20 texture units and 5 SIMDs round out the limits of
its 3D gaming abilities.
AMD Socket FM1
Both AMD A8 & A6 Fusion processors are compatible with AMD
905-pin 'Socket FM1' motherboards. As you would expect, Socket FM1
processors are NOT backwards compatible with socket
754/939/940/AM2/AM2+/AM3/AM3+ platforms or vice versa.
Thankfully, AMD hasn't given up on its longstanding dedication
to upgradability - users can install just about any heatsink manufactured
in the past 8 years onto a socket FM1 CPU. The AMD heatsink retention cage
hasn't changed, so socket FM1 and Socket AM2/AM3 heatsinks are entirely
interchangeable. Thermal design power (TDP) is a modest 100 watts for the AMD
Fusion A8-3850 PCSTATS is testing the Gigabyte GA-A75-UD4H motherboard with.
Next up, a 360 degree look at the Gigabyte
GA-A75-UD4H motherboard, then it's onto overclocking.