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Creative Labs 3D Blaster GeForce 3 Ti200 review

 

Stability

Before moving onto anything else I'll tell you about my experiences with the GeForce 3's stability out of the way. Personally speaking, stability of a Graphics Card (Or other Hardware/Software) is the most important feature to me and given my experiences from various newsgroups & e-mails I've received I was a bit nervous about how stable the GeForce 3 would be.

Before receiving this Graphics card I had received Windows XP & was a bit anxious about installing the latest NVIDIA Drivers after noticing this story on The Inquirer regarding the 23.11 Drivers. Thankfully I didnít have any problems with the new features in the Driver & VIA also responded with a patch quickly to circumvent any possible problems also (Though not Intel or Sis, Ali as far as Iím aware).

The stability of the Drivers was good, although not without issue and I did experience problems with some Games, e.g. when running the timedemos on Quake 3: the game would crash sometimes when changing resolution. At another point Serious Sam wouldnít load for some reason

 

Texture Compression

The GeForce 3 supports DXTC & S3TC Texture compression modes, although disappointingly the GeForce 3 was allowed to inherit the same fault as the GeForce 1 & 2 had: the DXT1 problem. The problem is that in the GeForce 3 DXT1 uses only 16-Bit interpolation, while other Graphics Cards use higher interpolation depths. As a result any DXT1 compressed textures with the GeForce 3 (Or 1 & 2 for that matter) look hideous. The most commonly used example to illustrate this is the sky in Quake 3. NOTE - S3TC=DXTC, albeit DXTC is used in Direct3D while S3TC is used in OpenGL, although other than that no differences exist, both use the same 5 Compression algorithms (DXT 1 - 5).

A workaround of sorts however does exist for this problem in OpenGL only. The NVIDIA driver team added a workaround whereby DXT1 requests are changed to DXT3 instead. It must be stressed this is a workaround only & that DXT3 offers poorer a compression ratio than DXT1. The screenshots below illustrate the Quake 3 sky with Texture compression disabled, then Enabled without the Workaround in effect, then with the Workaround enabled.

For sake of comparison I've also thrown in a shot of the same scene using a Vivid! XS Kyro 2 that supports DXT1 only.

Uncompressed

DXT1 Compressed

DXT3 Compressed

Kyro 2 - DXT1 Compressed

The Screenshots are fairly self explanatory as you can see, the Sky with the Kyro 2 Graphics Card looks fine, albeit with a small amount of colour banding (Noticeable with all Graphics Cards I might add) while the DXT1 compressed Sky on the GeForce 3 is a rather highly banded mess.

I've asked NVIDIA (Brain Burke & Diane Vanesse specifically) for some comments on this matter a few times over half a year ago, although to this date I've never received any reply/acknowledgement to my Questions (One of which being would the GeForce 3, unannounced at the time, have resolved this issue).

On Sharkyextreme NVIDIA did make some statement on the matter, that being "It works according to spec". This is partially true as the DXTC spec makes no mention of what interpolation to use for DXT1, but anyone with a basic sense of logic can figure out that in order for Texture compression to be viable it must compress textures with a minimum amount of perceivable artefacts, something which NVIDIA has failed to pick up on sadly. Epic's Daniel Vogel had the following to say over on GameBasement about the matter (Partially in response to the previous NVIDIA claim that it works correctly);

They don't work according to the specification & the below is just PR talk. I doubt you would get one of their developers to state that the texture compression works according to the specs & even if it were working according to the specs (which it is not) it wouldn't be an argument as every other company has better DXT1 support.

It wouldn't matter if it were working "correctly" if it is looking worse than ATI's. The average gamer doesn't care about technical details - she/he wants nice looking graphics on her/his screen.

You can read the full article on about DXT1 on NVIDIA GeForce 1/2/3 Graphics Cards over at Gamebasement.

Performance wise I did a quick test in Quake 3 & using DXT1 the average frame rate was 141.9, whereas with DXT3 (workaround) the frame rate dropped slightly to 140.6. That said the difference will be more noticeable in Games which use a greater amount of DXT1 compressible textures.

Anyway, the point to get from all of this is that DXT1 on the GeForce 3 does not work correctly. It does not do what texture compression was intended to do Ė reduce video memory storage size with minimal image quality difference. Whereas NVIDIA may insist it works according to spec the fact that newer Drivers contain a workaround in the OpenGL driver for this would seem to indicate even they realise itís a problem. Letís hope the next GeForce finally can perform DXT1 compression properly, in much the same way that the PowerVR Kyro 1/2 can.

 



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