ATI Radeon 5770 Roundup

Now that the first wave of DirectX 11 games are hitting store shelves, gamers looking to upgrade their PCs are increasingly eyeing DX11 graphics cards like ATI’s Radeon 5000 series. Unfortunately what they’ll find is that cards are still hard to come by – particularly if you want a Radeon 5850 or Radeon 5870 – and that prices have gone up: all of ATI’s recently released 5000 series cards have seen their prices increase since they were originally launched, including ATI’s newest mainstream additions the Radeon 5750 and 5770.

It’s the Radeon 5770 that we’re most interested in today.

The Radeon 5770 is ATI’s performance option for the mainstream segment of the graphics market. In terms of specs, it’s configured most similarly to ATI’s Radeon 4870, which it essentially replaces in ATI’s lineup. It has the same 800-shader architecture as the 4870, and the same number of texture units and ROPs as its predecessor as well. The Radeon 5770 is actually clocked a little faster than the 4870, with the graphics core running at 850MHz (versus 750MHz for the 4870), which helps give it a slight advantage in terms of texture and pixel fill-rate.

ATI also happily boasts its superior compute ability – 1.36 TeraFLOPS – although in all honesty this figure means very little for gamers.

What is important -- particularly if you game with anti-aliasing -- is the board’s 128-bit memory interface. That’s half as wide as the 256-bit memory interface found on the 4870. ATI tries to compensate for the narrower memory interface by cranking up the memory speeds to 1200MHz (300MHz higher than the 4870), but the cumulative effect is that the 5770 is still giving up nearly 40GB/sec of memory bandwidth to the 4870.


As you can imagine, that’s an awful lot of memory bandwidth to be giving up to a card the 5770 is supposed to be replacing. And as a result, the 5770 isn’t able to keep up with the 4870 in most of today’s games. It generally trails by anywhere from 7-14% depending on the game being tested as well as the screen resolution.

This has pushed a lot of gamers in the mood to upgrade to pick up Radeon 4870 or NVIDIA GeForce GTX 260 cards. These cards may not support DX11 like the 5770, but they cost about the same or less than the 5770, and perform better with today’s games, which are largely based on DX9 or DX10 game engines.

If you’re upgrading for the long haul though, and need a card that will last you for a year or more, DirectX 11 support becomes more important. As we showed you in our Radeon 5770 Performance Preview article, benchmarks with a DX11 title like BattleForge illustrate how the 5770 can leverage DX11 to gain a performance advantage over the Radeon 4870.

With this in mind, we’ve gathered a pair of Radeon 5770 cards that should appeal to different demographics.

For the performance-oriented enthusiast, ASUS’ Radeon 5770 Voltage Tweak offers the ability to adjust the GPU’s voltage, potentially allowing you to OC the card further than your average Radeon 5770. Meanwhile PowerColor’s Radeon 5770 board should appeal to the value-conscious user who wants to save some money.