HIS Radeon HD3870 Review & Crossfire Performance Preview

A closer look at the HIS Radeon HD3870


Well, here it is; the star of the show. As is usual for ATI cards, the HD3870 is decked out with a red PCB and a red plastic dual-slot cooler. While it looks quite long when looking at these pictures, it is exactly the same length as the previously-reviewed 8800GT which is “only” 9”. Unfortunately, the PCI-E power connector sits at the back of the card so you will need to add another ¾” to the overall length once the power connector is installed. This card is supposed to have a sticker over the main expanse of plastic on the heatsink but HIS received these cards a bit too late to finish developing their graphics. Expect future cards to come with some form of sticker which covers the top of the cooler.

You can see that the heatsink itself is a relatively simple forced-air affair with a large intake fan which blows cool air over a stack of copper fins placed directly over the core. The hot air is then exhausted out the back of your case which keeps interior temperatures under control. Due to the relatively low amounts of heat produced by the 55nm RV670XT core, the cooling solution can be kept quite minimal and lightweight.


There are quite a few interesting points about this heatsink assembly that should be mentioned. First of all, the pure copper heatsinks on the ram are completely independent from the rest of the cooler. This can present some very interesting options for people who will install an aftermarket cooler on this card since in some cases they can be left exactly where they are. Personally, I think this is absolutely brilliant and I will be putting this to the test a bit later in this review with the installation of an aftermarket cooler.

The fan itself is a very large 13-bladed affair that carries an HIS sticker on its central hub. ATI’s coolers have been much-maligned for being too noisy under any load condition but supposedly this new fan blade layout makes this fan one of the quietest around. Like past models, it is on a fan-speed controller which is directly linked to the temperature sensor on the core.


Even though this card can be used in the new “Crossfire X” setup which daisy-chains up to four HD3870 or HD3850 cards together, the Crossfire connector on this card is no different than that of the HD2900XT. There are two connectors, both of which need to be hooked up to another card via a Crossfire bridge if you want to enable Crossfire.

The back (or is it front?) of the card holds the metal grille used to exhaust hot air along with a pair of DVI connectors and an HDTV-out connector.


The underside of the HIS Radeon HD3870 doesn’t hold much of interest but it should be noted that the main heatsink is only held on by the 4 screws surrounding the x-shaped contact plate. The other screws you see here are holding down the memory and VRM heatsinks.


Under the heatsink of the HD3870

Please note that removing the heatsink WILL void your warranty


After the heatsink is removed we once again see that the memory and VRM heatsinks are completely independent from the main cooler. Speaking of the main heatsink, I find that the area where it contacts the RV670 core needs to be revised a bit since it is far from flat and very rough when you touch it.


Even though the memory heatsinks are copper, the heatsink over the VRMs is made of brass colored aluminum.

At the heart of the HD3870 lies the 55nm RV670XT core. Unlike the cores from other cards, there is nothing printed on this one to distinguish it as being of the RV670 family.