Index
Review: An overclocked reference design
Today we’ll look at a graphics card that’s not too different from the reference HD 4870 card, but what makes it particularly interesting is the source partner. If this is the first time you’ve seen Radeon cards in XFX’s offer, then you probably haven’t been watching the industry closely as these guys already offer all the latest Radeons. We’ve recently had a chance to test XFX’s overclocked HD 4850 with non-reference cooling, and you can learn more about it here.
XFX Radeon HD 4870 comes codenamed as HD 4870 775M 1GB DDR5 Dual DVI TV PCI-E XXX. This quite long name goes a long way in explaining what the card is about, and 775M means 775MHz, meaning it’s overclocked and XXX suffix is another proof of that. Still, this is only a 25MHz overclock but with the 3800MHz memory, this card packs enough of a punch to be called a great gaming graphics card.
XFX’s HD 4870 775M card comes with XFX’s sticker, but they’ve also ended up using a black PCB combined with red DVI outs, as opposed to red PCB and white DVI outs on the reference card. Thanks to this color scheme, courtesy of XFX, the card looks much more aggressive than the reference one.
You’ll find 1GB of GDDR5 underneath the hood, and it is already considered an optimum for playing the latest game titles. The cooler is dual slot, the same one found on the reference card. It runs quiet in idle and although 3D mode can result in higher noise levels, it’s still not what we’d call too loud.
Note that GDDR5 memory offers twice the bandwidth per pin compared to GDDR3/4 memory, provided it runs at the same clocks of course. So, although a 256-bit memory interface ended up being used, GDDR5 enabled a bandwidth of 115.2GB/s. Bear in mind that this card’s fierce competitor, the GTX 260, comes with GDDR3 and offers 111.9GB/s bandwidth, despite the 448 bit memory interface.
Radeon HD 4870 uses the RV770 graphics processor built in 55nm. It has 800 shader processors and 40 texture units, which is 2.5 times more than HD 3800 generation offers on both fields. The rest of the important specs can be seen on the GPU-Z picture below.
RV770 offers 7.1 audio as well, courtesy of Realtek HD Audio processor which is integrated directly into the GPU silicone. There’s no need for additional cables, unlike Nvidia’s offerings where you’ll be using a SPDIF cable to bring the audio to the card if you want to send both video and audio to your HDTV device via one cable. This card provides HDMI via the provided DVI-to-HDMI dongle and the I/O panel features two dual-link DVI outs as well as S-Video out. UVD 2 video decoding engine will also provide benefits such as options dual-stream decoding and dynamic contrast enhancement.
A good thing about this cooler is that it pushes the air outside of the case, thus surely making life easier for the rest of the in-case components. The fan is located towards the end and blows air trough the aluminum heatsink and towards the air outlets on the I/O panel.
Two 6-pin PCI-Express connectors power the card, and they’re located in the corner towards the end of the card.
XFX packaging comes as refreshment, as it’s a step away from the usual large packaging we’re constantly seeing, and we often ask ourselves whether such large boxes are needed at all.
The box contains the usual stuff – DVI-to-HDMI converter, DVI-to-VGA converter, 2x molex to 6-pin PCI-E cable, Crossfire Bridge, a short installation manual, the driver CD and of course, the graphics card.
