First Look: Sapphire Radeon HD 4850 X2 2GB

Manufacturer:Sapphire
UK Pricing: £300 (inc. VAT) – estimated

Core Clock: 625MHz
Memory Clock: 1,986MHz
Memory: 2 x 1,024MB GDDR3
Warranty: Two years (parts and labour)

When AMD released the ATI Radeon HD 4870 X2, the company talked about another dual-GPU product designed to compete directly with Nvidia's GeForce GTX 280. That product was the Radeon HD 4850 X2, but at the time AMD didn't put any kind of timeframe on the release.

In fact, when I spoke to AMD about the Radeon HD 4850 X2 about a month ago following its non-existence, I was told that it would be a "partner-only" card and that there wouldn't be a reference design. That's fair enough I guess because it is, after all, the partners that are selling graphics cards to consumers – or at least that's the case in the UK.

Sapphire is the first company to announce a Radeon HD 4850 X2 and it says that it is "exclusive to Sapphire." This is something that occasionally happens, but Sapphire wasn't the first add-in-board partner to talk to us about the 4850 X2 – it was merely the first to get hardware to us.


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Maybe Sapphire has a timed exclusive on hardware in the channel or maybe the partners we'd spoken to have now been told that they're no longer allowed to release cards based on the Radeon HD 4850 X2? I don't know the full answer, but I'll endeavour to do a bit of digging – I guess we may see more partners announcing Radeon HD 4850 X2 based products over the coming weeks or months if it happens to be because of the former.

The card has the same number of stream processors as the Radeon HD 4870 X2, which means there are two 'full' RV770 GPUs under the heatsink each with 160 five-way shader units (making a total of 1,600 stream processors over the two GPUs). The clock speeds are exactly the same as a single Radeon HD 4850 as well – the core is clocked at 625MHz, while the GDDR3 memory runs at 1,986MHz. Interestingly, Sapphire has included 1GB of memory per GPU, instead of the 512MB on a standard 4850 – we've heard that Sapphire is planning to release a 1GB version of the 4850 X2 in the future as well, but we don't have any pricing details for it.

Since the card arrived particularly late last week and the fact we're in the process of introducing some of the latest games to our test suite, while also re-tooling our graphics card testing systems with a couple of Core i7-equipped X58 motherboards, we haven't had time to give this card the full review it deserves. What's more, AMD hasn't released official drivers for Sapphire's Radeon HD 4850 X2 yet and so you'll be limited to using the pre-release drivers provided in the box until AMD introduces support in the official Catalysts.


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These drivers are, to be frank, a little flaky in some scenarios so we feel it's better to hold back before really gauging how well the Radeon HD 4850 X2 performs. Sapphire tells us that official driver support is forthcoming but whether it'll be the Catalyst 8.11 or 8.12 drivers that add the 4850 X2 isn't clear at the moment. With all of this in mind, we have tested the card in a couple of games to give you an idea of what to expect – there will be a full review as soon as we've got all of the above out of the way.

Sapphire has chosen not to use the Radeon HD 4870 X2's reference design PCB—probably because of the different traces required from the GPU(s) to memory—and has instead opted for its own design. However, rather than dive in and take the board apart for a full examination at this stage, we've decided to hold off on that until we come around to fully reviewing the card – rest assured that we'll be disassembling and poking around the board like a kid with his favourite new toy.

What we will say though is that Sapphire's 4850 X2 is longer than the Radeon HD 4870 X2 reference design (283mm compared to 267mm), which means that it will not fit in every chassis out there – be sure to check that you have enough room for the card to fit in your case. Like the Radeon HD 4870 X2, there are still a couple of power connectors—one six-pin and one eight-pin—and both need to be connected for the card to operate.


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There are a couple of 80mm fans attached to an aluminium shroud with Sapphire's branding emblazoned onto it. There are a couple of aluminium heatsinks on the two RV770 cores and a third heatsink that sits atop the PCI-Express switch positioned between the two GPUs. In addition, there are another couple of heatsinks on the power circuitry (one on the front and one on the back) that makes sure the PWMs are kept cool. Normally, we'd be a little concerned about a relatively tall heatsink placed on the back of the card covering additional power circuitry, but because of the card's length, it shouldn't cause any problems.

On the PCI bracket, Sapphire has done what Asus did with the Radeon HD 3870 X2 – it has implemented four dual-link DVI connectors that will certainly please multi-monitor lovers because you can not only run CrossFire, but also connect up to four high-resolution digital displays. The bracket is rounded off with an analogue TV-out connector – Sapphire has included composite and component adapters in the bundle.

And while we're talking about the bundle, Sapphire has included a pretty good selection of items in the box. In addition to the aforementioned cables, there is a DVI-to-HDMI dongle, a DVI-to-VGA connector, two supplementary power connectors, a CrossFire connector and a selection of software that includes Cyberlink PowerDVD, DVD Suite and 3DMark Vantage.