Sapphire Radeon HD 4850 X2
| Manufacturer: |
|
| Price: |
£300 inc VAT |
| Reviewer: |
Antony Leather |
| Review Date: |
Nov 2008 |
| Speed | 35/40 | 88% |
| Features | 24/30 | 80% |
| Value | 23/30 | 77% |
| Overall |
82% |
Verdict: [+] Inferno
Faster than GeForce GTX 280 in most games; cheaper than GTX 280; nearly as
fast as HD 4870 X2[-] BonfireCooler doesn't exhaust much air from the case; cooler is noisy; will ATI keep up the driver support?
Rumours of the ATI Radeon HD 4850 X2 have been around for some time and at one
point we thought ATI’s fifth dual GPU graphics card might not see the light of
day. However, Sapphire has proved us wrong by being the first manufacturer to
make a card sporting two Radeon HD 4850 GPUs on one circuitboard. The design of
the Radeon HD 4850 X2 2GB is Sapphire’s own, hence the blue PCB and the unusual
cooler.
The ‘X2’ range of
Radeon cards has been a rollercoaster ride however, with the ATI
Radeon HD 3870 X2 proving to be a very disappointing piece of hardware. With
poor minimum frame rates in games even when compared with single-GPU Radeon HD
3870 cards, the vastly more expensive card actually felt slower than its
single-GPU counterpart.
Conversely, the ATI Radeon
HD 4870 X2 was much more potent, gaining ATI the performance crown and making
short work of Crysis even at 1,920 x
1,200. However, this card ran so hot as to burn probing fingers trying to
remove it, and driver support from ATI was lacking until the recently posted
Catalyst 8.10 Hotfix driver.
It seems that ATI
is gradually getting the hang of these dual-GPU cards though, making the HD
4850 X2 and intriguing piece of hardware. It’s priced to undercut Nvidia’a
GeForce GTX 280 and ATI is confident it can beat this card for performance
too.
SPECIFICATIONS
Using two HD 4850
GPUs on a single PCB, the HD 4850 X2 has a huge 2GB of GDDR3 RAM clocked at 993MHz
(1.986GHz effective). The GPU itself is clocked at 625MHz so GDDR3 and GPU
speeds are identical to a standard HD 4850. However, standard HD 4850 GPUs only
have 512MB of GDDR3 memory each, not 1GB each as with the GPUs of the HD 4850
X2.
Sapphire has used
two 75mm fans with its own-design cooler, and these blow directly down onto the
two separate heatsinks that sit on each GPU. The cooler is open at both ends,
though as the card has four DVI ports there’s only a small amount of space for
heat air to be exhausted from the rear of your case.
As hot air is
also expelled from the card via a vent near the power connectors, the card
could potentially chuck hot air all over your hard disk(s) as it did in our
test PC. The cooler didn’t prove to be particularly quiet either.
The PCB of the HD
4850 X2 is huge – 11in (28cm) long so this may rule out fitting it in many
cases to start with. An 8-pin and a 6-pin PCI-E power connector are present and
both must be filled to use the HD 4850 X2.
Luckily the power
connectors are mounted on the fan side of the PCB rather than at the back. The two
power cables therefore hang directly down from the card, rather than jut out
from the side or rear.
HOW WE TESTED
We compared the
HD 4850 X2 against its nearest rivals, which include:
- An ATI HD 4870 X2
- An ATI HD 4870
- A pair of HD 4850s in CrossFire
- An Nvidia GTX280
We also tested a
single HD 4850 to see how much better the HD 4850s in CrossFire and the HD 4850
X2 are.
We were
particularly interested in Sapphire’s claims that the HD 4850 X2 isn’t much
slower than a HD 4870 X2. Given the latter’s
current price of over £350 inc VAT,
the £300 price tag we were quoted by Sapphire for the HD 4850 X2 is a tempting
one if this proves to be true.
ATI has released
an
8.10 hotfix driver
since we completed testing but due to time constraints we had no time to
re-test with this driver. We therefore used Catalyst 8.10 to test the HD 4850,
HD 4870, two HD 4850’s in CrossFire and the HD 4870 X2 and 8.11 BETA driver provided
by Sapphire for the HD 4850 X2. The GeForce GTX 280 was tested with the
ForceWare
178.24 driver.
We used Call of
Duty 4, Race Driver: GRID and Crysis at four different resolutions and levels of
AA and AF for our gaming performance tests. We used the Canyon Flight test of
3DMark06 for and indication of peak power consumption when gaming. We also ran
the
Stanford
Folding@home GPU client on all the cards, measuring ppd and power
consumption.
PERFORMANCE
Click here to open
the benchmark graphs (opens in new window)
Call of Duty 4
CoD4 works particularly
well with both CrossFire and SLI, so it came as no surprise to see the two dual
GPU graphics cards scoring well. At 1,680 x 1,050 the HD 4850 X2 ran the game
at a minimum of 79fps, 29fps faster than the GTX 280 and 28fps faster than two
HD 4850s in CrossFire. Only the HD 4870 X2 was faster, with its minimum of
96fps.
At 1,920 x 1,200,
the HD 4850 X2 recorded a minimum frame rate of 65fps – more than double the
29fps minimum recorded by the single HD 4850. The HD 4850 X2 was again second
only to the HD 4870X2 which recorded a minimum frame rate of 76fps.
The nearest
contenders were the two HD 4850s in CrossFire and the HD 4870 which both managed
minimum frame rates of 42fps. The GTX 280 could only manage a minimum of 41fps,
some 24fps off the pace of the HD 4850 X2.
Click here to open
the benchmark graphs (opens in new window)
Crysis
At 1,920 x 1,200 Crysis
is a tough test indeed and only the HD 4870 X2 could manage a playable minimum
frame rate of 25fps. The GTX 280 came in second with a minimum frame rate of
22fps, while the HD 4850 X2 could only manage a minimum frame rate of 19fps.
This is much
better than the two HD 4850s in CrossFire with which the game frequently
stalled completely resulting in the minimum frame rate of 0fps even if the
average was a more respectable 26fps.
Dropping the
resolution to 1,680 x 1,050 saw the GTX 280 come out on top, with a minimum
frame rate of 32fps. At this resolution the HD 4850 X2 still struggled, only
managing a minimum of 23fps – the pair of HD 4850s in CrossFire performed
almost identically. The HD 4870 X2 didn’t fare much better with a minimum of
26fps.
Click here to open
the benchmark graphs (opens in new window)
Race Driver: GRID
Race Driver: GRID
again appeared to favour CrossFire particularly at high resolutions. At 1,920 x
1,200, the HD 4850 X2 recorded a minimum frame rate of 98fps, making it 46 per cent
faster than the GTX 280 and its minimum frame rate of 67fps.
The HD 4850 X2 is
just nine percent slower than the HD 4870 X2 which recorded a staggering minimum
frame rate of 108fps.
The pair of HD
4850s in CrossFire managed a respectable minimum frame rate of 95fps, only a negligible
3fps slower than the HD 4850 X2. Meanwhile a single HD 4850 can run GRID at
1,920 x 1,200 at a minimum of 58fps.
Click here to open
the benchmark graphs (opens in new window)
OVERCLOCKING
PowerStrip,
Rivatuner and
AMD
GPU Overclock Tool all failed to overclock the HD 4850 X2, but the OverDrive
section of the Catalyst Control Centre did work. Using this we pushed the
memory from 993MHz (1.986GHz effective) to 1.15GHz (2.3GHz effective).
The GPU frequency
slider bar would only go to 700MHz (from 625MHz) and we found the card to be
stable with the GPUs running at this frequency. It’s possible that there’s more
headroom here, although even this large overclock did little for Crysis. At 1,280x1,024
the minimum frame rate increased from 28fps to 30fps and at 1,680x1,050 it
increased from 23fps to 24fps.
FOLDING AND POWER CONSUMPTION
We returned the
HD 4850 X2to stock frequencies for these tests. Even so, the peak power
consumption of 436W of our test system with the HD 4850 X2 installed is high,
although still 33W less than two HD 4850’s in CrossFire and 8W less than the
GTX 280.
Power consumption
while running Folding@Home was the highest of any graphics card on test at 385W,
even the HD 4870 X2. However this is explained by the high 2,287ppd compared to
the meager 1,894ppd of the HD 4870 X2.
The HD 4850 X2 is
clearly working harder than the HD 4870 X2, though ATI couldn’t confirm whether
or not this was because the Folding@home client was addressing both GPUs of the
HD 4850 X2 and only one of the HD 4870 X2.
However, even the
ppd of the HD 4850 X2 is nowhere near the huge 6,430ppd recorded of the GTX 280.
It seems Nvidia GPU’s are still the way to go for folding.
CONCLUSION
ATI is clearly
pitching this card straight at the Nvidia GeForce GTX 280 with a price to
undermine it and performance to surpass it in most games. Only the freakish
Crysis holds the HD 4850 X2 back.
The price could
prove a potential downside, as two HD 4850s cost roughly £100 less than the HD
4850 X2 – many would think that either setup is equally as good. However, they’d
be wrong for thinking this, as our benchmark results prove.
The pair of HD
4850 cards deliver erratic performance, with minimums sometimes dropping
dramatically. In contrast, the HD 4850 X2 has more consistent performance, and
often higher performance too. That the HD 4850 X2 is a single card and doesn’t
require a CrossFire-compatible motherboard is also a boon.
The cooler is a
concern however. You’ll need ample exhaust fans to deal with the heat that the Sapphire
Radeon HD 4850 X2 dumps into your case. Furthermore, you might find that the rear
air vent of the card points towards your hard disk, making it advisable to move
the disk to another bay if possible.
The latest
drivers appear to have focused on the HD 4870 X2 and HD 4850 X2 specifically
and we had no issues with stability with either card which is great news. It’s
worth noting that the HD 4870 X2 didn’t receive a driver update for months
after it was released and the same could be true of the HD 4850 X2. Only time
will tell, but the HD 4850 X2 makes a good initial impression and elbows the
GeForce GTX 280 into third place in the fast GPU rankings.
