XFX Radeon HD 4770 512MB
As with both previous HD 4770s we've looked at, the GPU is a reference RV740 design with 128 five-way superscalar shader units (or 640 stream processors) with the chip being manufactured on a TSMC 40nm process resulting in less power consumption, heat and ultimately greater overclocking potential.
Smaller manufacturing processes usually result in good things in addition to a more efficient design and ATI has managed to achieve some fairly high clock speeds with the HD 4770. The GPU is clocked at 750MHz -125MHz faster than the HD 4850 and is actually the same as the Radeon HD 4870's RV770 chip.
The Gigabyte ATI Radeon HD 4770 512MB proved to be somewhat of a cut down card compared the reference one we received with plenty of capacitors missing and the cooler had no direct contact with the RAM. This is true of the XFX ATI Radeon 4770 512MB as well but unlike the Gigabyte ATI Radeon HD 4770 512MB, the cooler on the XFX is able to exhaust hot air from the GPU straight out of the back of the case. This is clearly a better design than that found on the Gigabyte which will just dump the heat into the case, relying instead on your case's airflow to get rid of it. The XFX's fan features PWM control, something else the Gigabyte doesn't have.
However, we noticed that the PCB looked a little sparse compared to the reference card and sure enough, XFX has also decided to strip a few capacitors off the PCB. We also noticed that the RAM is not in contact with the cooler and what's more, much of it has no direct air flow unlike the Gigabyte.
Luckily the RAM chips don't get that hot and even during our Crysis
benchmark they were only slightly warm to the touch. Our initial reservations with the Gigabyte card proved to be unfounded as it was not only able to keep up with the reference card but was also a stunning overclocker. At this moment in time we don't have any major concerns with this design and this is backed up by the fact the HD 4770 is a cool running card and didn't suffer from any artifacts or other visual corruption at all during our benchmarks.
One last thing to note is the SKU number. We found that when writing this article, a number of very different looking XFX Radeon HD 4770 512MB cards were on sale with different SKU numbers. In short, XFX told us that SKU numbers HD-477A-YDFC which is a standard box, or HD-477A-YDF7 which is the same as our X-shaped box both have the same cooler and same accessories.
However a third code, HD-477A-YDLC, has been around for a while and refers to a version with a different cooler so make sure you buy the right card. If in doubt check with the retailer because at the moment the latter is more commonly found online but new stock will consist of graphics cards with the new SKUs and the better cooler.