The most impressive reference cooled overclocking core we’ve seen!
Graphics card overclocking is no recent phenomenon for Atomic, as we've been doing it since before we even left the womb. But what astounds us about this card, as we'll explain in a minute, is that it can overclock exceptionally in ways that back in the day we'd never dream of. First things first though, so let's look at the tech running inside this $155 budget card as it runs up against NVIDIA's 9800GT.
The 4770 is built around the incredibly new RV740 core, the very first desktop core to be manufactured entirely in a 40nm process. Yes - this is a smaller size than even the top Intel/AMD chips can manage! It's got only 640 shader units when compared to the higher-end cards, but they're still clocked at a respectable 750MHz. The budget angle of the card means that the memory bus has also been cut down to only a 128-bit memory bus, but this is paired with 512MB of GDDR5 memory at 800MHz, giving a very good amount of bandwidth for a much cheaper price. Smaller memory buses mean simpler PCBs, and even less to get in the way in terms of electrical interference.
When we sent out our feelers, XFX responded immediately and sent us their version of the 4770 which not only comes with a decent dual-slot cooler but is actually the cheapest one on the market! It's a very special beastie; treated to XFX's typically premium black PCB coating, darkened PCI bracket and red accentuated DVI ports. The sticker on the card is colourful and tells you everything you need to know, removing any chance that you'll get confused as to which card it is.
Cooling is handled by a large aluminium base that contacts the very small die (only 137mm2) and rises simply into a series of aluminium fins. One 70mm fan at the end brings in plenty of fresh air, which is guided by the plastic shroud and exhausted at the back of the case. The Qimonda memory chips remain sadly uncooled by any heatsink, and they became quite toasty when overclocked, so make sure there's plenty of airflow inside the case. Idle temperature was a low 45 degrees at 56dBA, which rose to 58 degrees with momentary bursts to 69dBA; most of the time it remained at the lower 56dBA level.
We got to overclocking the card itself, and pushed it as far as we could take it on this reference cooler... This reference, aluminium, no heatpiped cheap little cooler. Boy, it impressed us. We hit a final core speed of 934MHz, an astounding 25 per cent increase! For such a budget card we certainly didn't expect anything near this awesome a result, and we even managed to eke out an extra 40MHz for the memory at this core speed!
Performance is incredibly attractive too for such a cheap card; priced identically to the 9800GT this card outperforms it across the board. Crysis was more than playable, both 3DMark benchies ran very well and even GRID did fairly well at the huge res we bench at (though there was some slowdown during cornering, thanks to extra smoke and other effects).
The bundle is nonexistent, at only a few cables and driver disc, but the real gold here is the RV740 core. We can only imagine what the future for graphics cards will bring when we move to this process; until then the XFX 4770 is a bloody good choice for any enthusiast or gamer.
Slicing the pieSilicon wafers currently used in production are 300mm in size, which give a surface area of 109.6 inches squared, or 2783.84mm2. Considering the size of the RV740 is 137mm2, this means that roughly 20 cores can be produced on a single wafer - compared to the G92b core in the 9800GT at a size of 230mm2 and only 12 dies. It's obvious to see how the price is so low when they're squeezing more dies from the same cost wafer!
Issue: 107 | December, 2009