84 |MAMAMAXIMXIMXIMXIMUUUUMMPPPCC| FEB 09 | http://www.maximumpc.com
IN THE LAB^
REVIEWS OF THE LATEST HARDWARE AND SOFTWAREA
s a general rule, our belief is that pairing
two slow-performing cards using SLI or
CrossFire is a bad idea—you’re usually
better off running a single faster card. However,
the Radeon 4850 X2 delivers astounding perfor-
mance compared to the single-GPU boards in
its price range, spanking the Radeon 4870 and
the GeForce GTX 280, with none of the pitfalls
that have plagued dual-GPU boards in the past.
At the heart of the board is a pair of ATI’s
RV770 GPUs running at 625MHz, just like thesingle-GPU in the 4850 boards. Each GPU
features a full complement of 800 stream
processors, which are connected to identical
1GB GDDR3 frame buff ers running at 993MHz
on a 256-bit bus. Although X2 boards are
labeled as featuring 2GB of memory, because
the contents of each GPU’s frame buff er must
be mirrored, applications can utilize only 1GB
of video memory.
Like its 4870-powered predecessor, the
4850 X2 sports ATI’s advanced video decode
acceleration, allowing you to
view fully accelerated picture-
in-picture Blu-ray discs. It’s fully
compatible with multiple-monitor
displays, and we love that this
board features four DVI ports for
multi-mon madness.
In our performance testing,
the 4850 X2 unseated the fast-
est single-GPU videocards, the
GeForce GTX 280 and Radeon HD
4870, in almost every bench-
mark. The exception to the rule
was Crysis at high visual-qualitysettings and high resolution. When running
at 1920x1200 with 4x antialiasing and the
visual-quality settings cranked to Very High,
we hit the 4850 X2’s memory bandwidth wall.
Despite running at a higher clock speed than
the 4870-family boards, the GDDR3 on the 4850
transfers half as much data per clock cycle.
With a street price that’s less than $300, the
4850 X2 is a great deal for owners of lower-res-
olution 22-inch monitors. However, if you use
a 24-inch or 30-inch panel, it’s probably worth
ponying up for a card with a pep-
pier memory pipeline. –W I L L S M I T HSapphire Radeon HD 4850 X2
A surprisingly speedy videocard powered by ATI’s midrange GPU
This Radeon 4850 X2 board sports twice as
many GPUs and DVI ports as its single-GPU
brethren —and twice as much cooling!Best scores are bolded. Benchmarks are run on an Intel Core 2 Quad Q9770 Extreme, with 4GB of memory running Windows Vista. Crysis, and 3DMark Vantage are run at 1920x1200, with 4x AA
and 8x anisotropic filtering, unless otherwise noted. Call of Duty is run at 2560x1600 with 4x AA.BENCHMARKS
Sapphire Radeon HD GeForce
4850 X2 4870 X2 GTX 280
Driver Version 8.12 8.12 180.48
Crysis 4X AA/Very High (fps) 12.41 29.6 18.35
Crysis No AA/Very High (fps) 27.87 31.6 22.28
Call of Duty (fps) 80.7 106.5 68.09
Far Cry 1920x1200 (fps) 60.3 68.5 52.2
Far Cry 1680x1050 (fps) 64.9 72.2 58.7
Vantage Game 1 (fps) 17.54 19.2 17.32
Vantage Game 2 (fps) 14.25 18.9 13.11+ -
VERDICT$330, http://www.sapphiretech.com9
Killer performance
for $300. Four DVI
ports! Faster than a
GTX 280.GDDR3 hurts memory
bandwidth. Four DVI
ports leave no room for
rear exhaust vents.EMERALDSSAPPHIRE RADEON HD 4850 X2AMETHYSTS