2D, Acceleration, And Windows: Aren't All Graphics Cards Equal?

Tom2D Benchmark: Radeon HD 5870 Vs. GeForce GTX 285 In Windows 7

With the help of this new benchmark, we hope to better understand the root causes for the 2D bottlenecks we’ve so recently discovered for the Radeon HD 5870, 5850, and 5750 cards we have at our disposal. To begin with, we proved to ourselves that 2D acceleration of GDI functions in Windows 7 definitely doesn’t work for any of these Radeon HD 5000-series models, rather than simply slowing down dramatically. Is it a driver or a hardware problem? Nvidia doesn’t come through this testing blemish-free, either: even for its cards, not all possible functions are truly accelerated.

In order to establish a better baseline for the purposes of comparing 2D acceleration enabled/disabled, we also ran all of our tests on an older nForce 610i chipset with integrated GeForce 7050 graphics (lacking an on-board frame buffer). We installed the same CPU and 4GB RAM, and used the same 64-bit Windows 7 operating system. We also substituted the predecessor to the Radeon HD5870, ATI's Radeon HD 4870, in our other test platforms as well.

Test 1: Rendering TrueType and OpenType

All candidates fall into the same narrow range for this test.

We would like to hear what Nvidia has to say about why its on-board graphics processor renders 2D graphics faster than a GeForce GTX 285, even if the difference is fairly modest.

Using the Radeon HD 4870 as a baseline control placed it in the bottom third of the pack, without showing any real weaknesses of which to speak.

Test 2: Drawing Lines

Surprisingly, the Radeon HD 5870 is simply incapable of rendering hardware-accelerated lines with any reasonable performance.

Whereas both of our test subject deliver acceptable and reasonably-close results with 2D acceleration turned off, leaving the job to the CPU, a substantial gap between the two cards opens up once we enable Aero. The GeForce GTX 285 runs as much as 11 times faster than ATI's Radeon HD 5870. Worse yet, an on-board graphics processor from a two year-old $50 motherboard bests this $400 graphics card by an order of magnitude.

Furthermore, our readings for the Radeon HD 4870 show little difference between Aero-enabled and basic (non-accelerated) Windows 7 graphics performance, suggesting no acceleration for drawing lines in Windows 7. This card is measurably slower than a GeForce GTX 285 and the on-board graphics solution, but is able to best the Radeon HD 5870 with acceleration turned on and off.