The A8-3850 processor is the culmination of AMD’s long- simmering Fusion architecture. AMD blended a quad-core CPU build (similar to existing
Phenom offerings) and poured in some
Radeon GPU goodness to create what the
company calls an APU (Advanced
Processing Unit). The integrated GPU is
the most ambitious graphics core built onto
a CPU chip yet, stuffing a full-on, low-end
DX11 graphics engine onto the processor.
AMD’s hoping the more advanced GPU
inside the A8-3850 will make up for the
somewhat anemic performance of their
traditional CPU cores.
Unfortunately, AMD’s also breaking
with tradition in a not-so-good way: the
APU procs require a completely new
socket (dubbed FM1), so if you want one,
get ready for a forced mobo upgrade.
Along with the new CPU, AMD’s shipping an updated Southbridge chip (a
The new APU procs still
have those fragile-as-hell pins. Be extra-careful handling!
shader cores running at 600MHz
plus 20 texture units. Sadly though,
compared to the Radeon HD 6770 (which
got a not-so-hot 68% last issue), this is half
the number of shader cores and a 250MHz
lower clock. Ouch.
It requires a completely
new socket, so get ready
for a mobo upgrade.
mobo’s Southbridge controls areas such as
USB and the BIOS), dubbed the Fusion
Controller Hub (or FCH). The higher-end A75 version of the FCH is the first PC
core logic to implement USB 3.0 and
SATA 6Gbps on a single chip. Pretty cool.
But it’s the A8 that’s the most interesting: the CPU itself consists of four traditional Phenom-style cores running at
2.9GHz. The graphics engine built onto
the A8-3850 runs in parallel with all those
cores. The integrated GPU consists of 400
It’s a Radeon,
the driver says so!
AMD calls the A8’s GPU a Radeon HD
6550D, but don’t be fooled by the naming
scheme: it’s not directly comparable to a
standard Radeon videocard due to the need
to share memory with the CPU. And when
memory sharing by two ordinarily separate
parts is required, you’re probably gonna see
a performance hit in both components—
which was unfortunately verified in my
tests. In fact, I couldn’t get the Shogun 2
benchmark to finish at all running at
1920x1080. The numbers in DiRT 3 and
Metro 2033 were OK for low-end hardware,
but certainly not jaw-dropping.
However, if 14fps in Metro 2033 at low
detail isn’t exactly awesome sounding, you
can always add an entry-level graphics card
for $120 or less, such as the Radeon HD
6670. The two GPUs then take advantage
of AMD’s CrossFireX technology,
improving framerates, and
allowing you to bump up the eye-
candy. In fact, when you install a second
low-end graphics card, AMD’s Catalyst
software sees the pair as a single Radeon
HD GPU. The HD 6670 plus the inte-
grated GPU becomes the Radeon HD
6690D2, for example. Of course, not all
games take advantage of CrossFireX, but
most current-generation games will see a
performance boost that’s almost doubled.
$135 ◆ www.amd.com ◆ Entry
OC TOBER 2011
OC TOBER 2011
#218 VOLUME 18, NUMBER 10 OC TOBER 2011