Board analysis

Other than the PCB color, both cards look very similar

The sticker is different too

At first glance, the Radeon 4870 X2 board looks almost identical to the Radeon 3870 X2 card we tested back in January. The only difference that is immediately noticeable is the black PCB.

ATI uses the exact same dual-slot heatsink/fan unit that was first built for the 3870 X2, and the board continues to measure 10.5”. Looking closer however we can see that ATI uses larger, more powerful capacitors for the 4870 X2. This is needed because the 4870 X2 board draws up to 286W of power.

Speaking of power, as you can see the card requires one six-pin PCIe 2.0 power connector and one four-pin connector. ATI places the connectors perpendicular to the edge of the board, just above the heatsink/fan cooling unit.


This location is definitely less than ideal in our opinion, we’d prefer it if the power connectors were located parallel to the edge of the board (like the conventional Radeon 4870) as most of today’s high-end power supplies ship with bulky PCIe power cables that are fairly thick. When two 4870 X2 cards are combined for 4-Way CrossFireX, it can be a little difficult mounting the lower card as you have to bend the PCIe power cables in order for the second 4870 X2 board to fit. Most X48 and X38 motherboards just don’t provide much room between the primary and secondary PCI Express graphics slots.

This can be a real bummer if you’re concerned about cooling and wish to run two Radeon HD 4870 X2 cards for 4-Way CrossFire, as there’s barely any space between the two cards. As a result, the uppermost card has a hard time drawing in fresh air, and ultimately it runs hotter. This in turn leads to the card cranking up the fan’s RPMs so the GPU can remain cool. Next thing you know the 4870 X2 cards are generating over 60 decibels of noise within your system.

And what about the temps? In our testing, a single Radeon 4870 X2 ran 66 degrees Celsius at idle, and 84 degrees at load. Considering that you’re running two GPUs on one card, these temps aren’t too bad in our opinion.


The beauty of a dual-GPU design like the 4870 X2 is that it gives you dual 4870 performance from a single PCIe graphics slot. You don’t need a CrossFire-compliant motherboard to take advantage of this feature, any board with a PCIe graphics slot works. Once the Radeon 4870 X2 is installed within your system and the drivers are loaded, the board automatically operates in CrossFire mode.


For added performance, the card can be mated to other 4800 series graphics cards: you can combine the 4870 X2 with a regular 4850 or a 4870, in addition to a second Radeon 4870 X2. When doing this however we recommend you use a Radeon 4850 or 4870 card with 1GB of memory. If you combine a 512MB Radeon 4870 card with the 4870 X2, the R700 GPUs on the 4870 X2 will only be able to page 512MB of memory.

1GB Radeon 4850 cards are available today, and we’ve been told that Radeon 4870 1GB cards will begin shipping later this month.

The Palit Radeon HD 4870 X2

The Radeon HD 4870 X2 cards we received for review today came from Palit. If you recall, Palit’s really been making a name for themselves lately among NVIDIA’s GeForce board partners with their custom board designs and cooling. Now Palit is taking that same approach for ATI’s Radeon GPUs.

The Radeon 4870 X2 cards available at launch today are all based on ATI’s reference design and cooling, but Palit has told us that they’re working on their own custom 4870 X2 board. In addition to better cooling, the board will also feature an 8-layer PCB (versus the 6-layer board used today), dual BIOS, and better capacitors. Palit also plans to OC their board for added performance.

Right now though all the boards are being produced by the same contract manufacturer, so other than price and game bundle, you won’t find many differences between the various 4870 X2 boards. We expect you’ll see the first custom 4870 X2 boards in September.