MaximumPC 2007 112

(Dariusz) #1

T


he good news for AMD is that its new
GPU is a much better graphics pro-
cessor than the absurdly power-thirsty
Radeon HD 2900XT that thudded onto the
market earlier this year. The bad news is
that AMD still can’t compete with either of
Nvidia’s high-end GPUs.
In fact, the prototype (and immature
drivers) that AMD provided us for bench-
marking proved to be quite a bit slower than
an EVGA 8800 GTS using Nvidia’s WHQL
drivers. AMD told us it hadn’t finalized the
clock speeds for the reference-design card,
and since Catalyst Overdrive had been
stripped from the driver we were provided,
we couldn’t tell what clock speeds the pro-
totype GPU and its 512MB of memory were
running at. (PowerStrip revealed only idle
clock speeds, which are ratcheted down
when the GPU isn’t under load.)

AMD hadn’t settled on pricing or even a
name for the RV670 before our print dead-
line (check MaximumPC.com for an update),
but reps for the company did tell us there
will be two versions of the new chip: An XT
with 512MB of GDDR4 memory and a dual-
slot cooler (the version we tested), and a
Pro with 256MB of GDDR3 and a single-slot
cooler. Both parts will have 320 stream pro-
cessors, the same number in the 2900XT.
Both SKUs will support a host of new
technologies, including PCI Express 2.0,
DirectX 10.1, and Shader Model 4.1, and
both will be equipped with AMD’s Unified
Video Decoder. UVD offloads all HD DVD
and Blu-ray video-decoding chores from
the host CPU. This feature is conspicu-
ously missing from the company’s top-end
Radeon HD 2900XT (high-end Nvidia parts
lack this hardware as well; you must step
down to the 8600 GTS to get hardware
decoding for HD). The new SKUs will also

support HDCP on Dual-Link DVI so that
30-inch panels can display copy-protected
high-definition video at their native resolu-
tions. They’ll also support VIVO for analog
video editing (another feature Nvidia’s hard-
ware lacks).
The new parts will support triple- and
quad-GPU configurations, provided you
have a motherboard outfitted with AMD’s
upcoming 7-series chipset and either
three or four PCI-Express slots (AMD has
dubbed this ATI CrossFireX). AMD prom-
ises support for Intel chipsets, too.
Thanks to its 55nm manufacturing pro-
cess, the RV670 draws considerably less
power than its older cousin. Our prototype
card had a single six-pin power connec-
tor and drew just 117 watts at idle and
208 watts under load, compared to the
2900XT’s 175 watts at idle and an insane
318 watts under load. A lower power draw
equals less heat dissipation, and that
means AMD will be able to specify a much
quieter cooler than the blow-dryer the
2900XT needs.
We’ll reserve final judgment on the
RV670 until we get a shipping product—
and see what Nvidia has up its sleeve—
but the new chip looks very promising
from many different angles. And that’s the
best thing we’ve had to say about AMD’s
GPU efforts in some time.

quick start The beginning of The magazine, where arTicles are small


AMD’s


RV


Rights


Many


Wrongs


08 MAXIMUMPC december 2007


Latest GPU draws less


power; piles on new


features


AMD’s Radeon RV670 could be a major
success—if it’s clocked and priced right.

Best single-GPU scores are bolded. AMD-based cards tested with an Intel D975BX2 motherboard; Nvidia-based cards tested with an EVGA 680i
SLI motherboard. Intel 2.93GHz Core 2 Extreme X6800 CPUs and 2GB of Corsair DDR RAM used in both scenarios.

3DMARK06 GAME 1 (FPS) 19.1 39.9 18.
3DMARK 06 GAME 2 (FPS) 17.1 33.9 19.
QUAKE 4 (FPS) 73.9 130.3 82.
FEAR (FPS) 46.0 84.0 61.
SUPREME COMMANDER (FPS) 22.4 41.6 26.

benchMARks


single RV670 RV670 xt single eVgA 8800
xt (512Mb) cRossfiRe (512Mb) gts (320Mb)
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