ATI and ASUS' latest is sittin’ on top of the manufacturing world.
The 4770 is ATI/AMD's sucker punch right into the 'nads of NVIDIA, screaming with all the fury of a karate-trained midget and striking fear deep into the heart of the green team. Because not only is this 4770 the first 40nm desktop card, it's also priced incredibly competitively compared to - and in most cases lower - than the 9800GT. It runs cool, is very cheap to manufacture and has a lot of overclocking potential, which has NVIDIA in a bit of a pickle for now.
The core that runs in the 4770 TOP is called the RV740, and it contains 640 shader units that run at an increased core speed of 800MHz, and 512MB of GDDR5 memory on a 128-bit bus at 850MHz. It's also got 826 million transistors, but takes up about the same amount of space as a stack of three ten cent coins! This is great for material cost, but also makes it much easier to actually cool the tiny little chip.
This card runs a dark red PCB with a single 6-pin PCIe power connector for external power, and the usual two Crossfire nipples at the top of the card. Up to four of these cards can be run together for a big performance increase, and you can also mix/match with other cards in the 48xx series. Two DVI ports and an analogue-out round out the expansion options, while the card interfaces with a 16x PCIe 2.0 slot on a mobo. This particular model comes with a new feature called Voltage Tweak, which is a software-controlled core voltage modifier that ranges from 0.95-1.25V, and should make it easier to get your overclocks stable.
The heatsink used on the card isn't the reference cooler, but is a custom designed copper model that looks almost like a less-elegant Zalman design. Fins extrude from the centre copper block and form a 'flower', inside which resides a single cooling fan. A plastic shroud is installed over this to channel airflow a little, but if you don't like it then four screws can remove the slightly-tacky plastic. There are no heatpipes or aluminium fins used in this design at all - the thermal output of the core is low enough not to need them. Strangely the memory chips aren't covered by a heatsink, and instead rely on the airflow provided by the fan to keep them cool. They got a little warm at stock, but nothing too disconcerting - after all, GDDR5 should run slightly cooler thanks to the lower voltage requirements. The heatsink kept the card at 40 degrees idle and 53.4dBA, with a load of 60 degrees and 55.6dBA.
Overclocking yielded a little extra performance, as we squeezed 865Mhz from the core (plus eight per cent) and a phenomenal 1200Mhz from the memory (A whopping FOURTY-ONE per cent). This was a very surprising result from the memory, giving us an effective speed of 4800MHz and a bandwidth of 61.4GB/s. Sure those memory increases aren't going to be anywhere near as noticeable as the core increases, but it's a very good sign that ASUS has used top-notch memory chips here, suggesting that the other components used might also be very high quality.
The bundle with this card isn't very astounding, only including the cables and driver CD, nor does the core manage to hit the 934MHz that XFX's offering did last issue - but it's still got good performance in all our benchmarks and games, with a decent increase over the reference design thanks to the small factory overclock.
Issue: 133 | February, 2012