Testbed and Methods

Our testbed was configured as follows:

• Intel Pentium 4 1.6GHz (400MHz FSB), Intel Pentium 4 2.8GHz (533MHz FSB) CPUs;
• ASUS P4S8X (SiS648) mainboard;
• 2 x 256MB PC2700 CL2.5 DDR SDRAM by Crucial;
• Reference graphics cards on SiS Xabre600, SiS Xabre400, NVIDIA GeForce4 MX440-8x; Sapphire RADEON 9000 64MB and Sapphire RADEON 9000 Pro 64MB graphics cards;
• Fujitsu MPF3153AH HDD.

We used the following software:

• Ver.3.07 driver (Xminator II) for Windows XP for graphics cards based on SiS chips;
• Ver.6.13.10.6200 driver (Catalyst 2.4) for Windows XP for graphics cards based on ATI chips;
• Detonator 40.72 driver for Windows XP for graphics cards based on NVIDIA GPUs;
• Windows XP:
• DirectX8.1;
• 3DMark 2001 SE build 330;
• Quake3 Arena v. 1.30;
• Serious Sam: The Second Encounter;
• Unreal Tournament 2003 v.2107.

We used the following settings for our benchmarks:

3DMark 2001 SE:

We set 32bit frame buffer; 32bit textures, 32bit (24bit) Z-buffer, D3D Pure Hardware T&L.
For High Polygon Count and Vertex Shader Speed tests: 640x480, 16bit textures, 16bit frame buffer, 16bit Z-buffer.
For Fill Rate tests: 1024x768, 32bit frame buffer / 32bit textures / 24bit Z-buffer and 16bit frame buffer / 16bit textures / 16bit Z-buffer.
For all synthetic 3DMark2001 SE tests we set the image quality to Normal in SiS Xabre600/Xabre400 drivers.

Quake3 Arena:

32bit screen and textures color depth. Maximum graphics quality settings. Tri-linear filtering and texture compression enabled.

Serious Sam: The Second Encounter:

We ran the tests in Normal mode: 32bit screen color depth. "Normal" graphics quality settings.

Unreal Tournament 2003 v.2107:

We tested with default settings.

In gaming tests the SiS Xabre600 based graphics card was tested in three modes: Performance, Normal and Quality. SiS Xabre400 based card was tested in Normal mode.

Performance

Synthetic Benchmarks

Let's start with testing the polygon processing speed:

SiS Xabre600, as well as Xabre400, shows excellent results. In case of one light source they lose only to NVIDIA GeForce4 MX440-8x, while in case of eight light sources the graphics chips from SiS are much faster than the competitors.

Xabre600 and Xabre400 perform T&L functions at the hardware level. It's proven by the fact that the use of a much faster Pentium 4 2800MHz instead of Pentium 4 1600MHz hardly told on their results.

Vertexlizer Engine, one of the strong points of Xabre600, is nothing more but software optimization of calculations with the help of the CPU. The test results bear the evidence.

Xabre600, as well as Xabre400 working at lower frequencies, and even NVIDIA GeForce4 MX440-8x, which differs from the by the absence of hardware vertex shaders processing unit, - they all show similar results. And these results are quite naturally determined by the CPU performance, not by the graphics chip vertex pipeline performance.

The graphics cards based on ATI RADEON 9000/9000 PRO chips have hardware vertex shaders support, so they run faster than other cards. Nevertheless, the high performance of Intel Pentium 4 2800MHz CPU helps the cards with no such support to catch up with the cards that have it.

The specialists from SiS must have been referring to this situation when they were talking about the absence of vertex shaders support in Xabre600, as about an advantage. A powerful CPU together with optimized drivers (Vertexlizer Engine) can bring Xabre600 to the level of graphics cards with fully-fledged vertex shaders support.

The texturing speed test brings no surprises. Xabre600 outperforms Xabre400 by a value corresponding to the difference in their working frequencies.

On the whole, the results of SiS Xabre600, one of the most well-armed chips of all present judging by the specs, are a bit disappointing. Although it has the highest working frequencies (315Mhz chip and 630MHz (315MHz DDR) memory), four pixel pipelines with two texturing units per each and 128bit DDR SDRAM memory bus, it's only a little ahead of ATI RADEON 9000 PRO, which has 275MHz chip and 550MHz (275MHz DDR) memory frequencies and four pixel pipelines with one texturing unit per each.

Regrettably, we have no miracle here and the release of Xminator II driver set didn't allow Xabre600/Xabre400 to become an equally powerful competitor to ATI RADEON 9000/9000 PRO.

NVIDIA GeForce4 MX440-8x has no hardware pixel shaders support and thus was not included into this test.

In the Advanced Pixel Shader test, both Xabre solutions have to build-up the scene in two steps as they don't have vertex shaders v.1.4 support, unlike ATI RADEON 9000/9000 PRO. So they lose even more here.

NVIDIA GeForce4 MX440-8x has no hardware pixel shaders support and thus was not included into this test, too.

3D Gaming Benchmarks

The gaming scenes from 3DMark 2001 SE come first. They were run in "Low Detail" modes. This is more appropriate for graphics cards of the Xabre600 class as "High Detail" mode loads the card much more and, what's more important, makes the results more CPU-dependent.

The graphics chips from SiS feel at ease in Car Chase: they outperform the rivals in any mode ("Quality", "Normal" or "Performance") and with the both CPUs: Intel Pentium 4 1600MHz and 2800MHz.

Anyway, the texturing quality provided by Xabre600 is lower than that provided by any other tested graphics card, although in the "quality" mode this chip performs "honest" bi-linear filtering, at least. 3DMark 2001 SE tests don't use tri-linear filtering so there is no significant performance drop by Xabre600 in the "Quality" mode, which might have been expected.

This test also depends a lot on the CPU speed. The test includes some elements of randomness and true physical models transformation. This, and not the Vertexlizer Engine, is exactly the reason why Xabre600/400 worked faster in the 600x800 resolution on transition to the more powerful CPU. The insufficient performance of Pentium 4 1600MHz had been limiting the results, while Pentium 4 2800MHz allowed the graphics chips from SiS to show their best.

In Dragothic Xabre600's superiority is no longer as indisputable as in Car Chase. Nevertheless, while Xabre400 was the slowest in 1024x768 and 1280x1024, Xabre600 could compete on nearly equal terms with the ATI RADEON 9000 PRO in these resolutions.

The CPU affects greatly the results of the cards in the "Lobby" test. Thus, the results are rather close to each other in 1024x768 and 1280x1024.

But we can see that in 1280x1024, when the CPU's limiting impact gets lower, SiS Xabre600, ATI RADEON 9000 PRO and NVIDIA GeForce4 MX440-8x do about the same, while SiS Xabre400 and ATI RADEON 9000 fall somewhat behind.

The "Nature" scene uses both: pixel and vertex shaders. The SiS' solutions execute pixel shaders very slowly, according to synthetic 3DMark 2001 SE tests, and as for vertex shaders, they don't support them on the hardware level at all. So, no wonder that SiS Xabre600 and Xabre400 just couldn't get close to the results shown by ATI RADEON 9000/9000 PRO.

The results also suggest that the software optimization of vertex shaders processing (Vertexlizer Engine) didn't help SiS graphics chips on transition to the faster CPU.

NVIDIA GeForce4 MX440-8x has no hardware pixel shaders support and thus was not included into this test.

SiS Xabre600 once again wins the race in Quake3 Arena, especially in higher resolutions, when the limiting impact of the CPU is less evident.

These results don't tell anything about the quality of the picture, though. And to tell the truth, it's a sore spot of all chips from SiS. The "Performance" and "Quality" modes don't even offer the ordinary bi-linear filtering, not to mention the tri-linear one. The driver simply ignores your attempts to enable it in Quake3 Arena settings.

And when the "Quality" mode is on (that is, bi-linear and tri-linear filtering are used), the results of Xabre600 drop down and it finishes the last of all.

But this is not the end. Remember that the texture quality by SiS Xabre600/400 is worse than by competitor products even in the "Quality" mode due to reduced level of detail (LOD). If we could set the texturing quality by Xabre600/400 to the level texturing quality provided by graphics chips from ATI and NVIDIA, namely, disable the "turbo-texturing" by setting TexTurboMode=0, we would get even lower results…

In the "Normal" mode Serious Sam: The Second Encounter game doesn't use tri-linear or anisotropic texture filtering. This doesn't help SiS Xabre600 at all. It wins the last but one place in all modes and is only better than its slow predecessor, the Xabre400.

Interesting numbers, aren't they? Xabre600 showed the same results as Xabre400, notwithstanding the higher frequencies of the newcomer. This may only be because of the CPU's limiting impact. Other graphics cards didn't notice the CPU performance increase, which is quite natural: Unreal Tournament 2003 in the Flyby mode loads the graphics card very well.

So, the cards based on SiS chips ended up in the end of the list. Seems like it's the insufficient optimization of the Direct3D part of the driver that is to blame here. On the other hand, we saw that SiS chips performed well in 3DMark 2001 SE. We can only think of one explanation: the Direct3D part of the driver was optimized exclusively for best results in 3DMark 2001.

As for image quality in Unreal Tournament 2003, we don't have any complaints here, except Xabre's usual texturing "delights".

Conclusion

So, SiS Xabre600 is really the fastest solution of all company's creations. The new chip showed 10-20% betterer results than its predecessor, SiS Xabre400.

The transition to the 0.13micron technology allowed increasing the frequencies above the expected level and thus raising the performance of the new graphics chip even more. It also means that SiS has no problems producing graphics chips with this fine manufacturing technology.

Among the advantages of Xabre600 we should mention DirectX8.1 support, high-quality TV-Out and multi-display configurations support, stable drivers and low heat dissipation.

At the same time, Xabre600 inherited the whole bunch of drawbacks from its predecessors. The most unpleasant among them is the low texturing quality in the "Performance" mode and low performance in the "Quality" mode.

As a result, Xabre600 can challenge graphics cards based on NVIDIA GeForce4 MX440-8x and ATI RADEON 9000/9000 PRO in its fast mode, but if we turn off the "turbo-texturing", Xabre600 will experience a big performance drop.

To sum up, the graphics cards based on the new Xabre600 graphics chip from SiS may become an appealing buy only if they cost less than cards based on NVIDIA GeForce4 MX440-8x or ATI RADEON 9000/9000 PRO.