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maha_x
08-17-01, 04:04 AM
Ive been looking trough load of kyro2 reviews and the seem to get very different results.

I think I looked over 10 reviews. Only two of them found out that enabling Trilinear filtering can lead up to 30% hit in performance. And only one of them found out also that using texture compression in Q3A seemed to remove the perf. hit. After going trough some forums it began to look like if the mem bandwidth is to be blaimed. The mem bandwidth theory has some drawbacks. The same hit in FPS is same even at 16bit rendering, alltought more mem bandwidth should be available. This leads me to think that the architechture itself needs more clock cycles to do the Trilinear. But why texture compression nullifies this? Mayby the bandwidth bottleneck is in the Kyro2 mem controller where the data is still rendered in 32bit. this could explain why the perf. hit occurs similarly on both, 16 and 32bit modes, but is helped with text.compression.

Another issue found is the DX8 bug which keeps Kyro2 from rendering into textures. It can do it, but DX8 bugs, so all attempts to do it resort to do it in software. One popular use for rendering into textures is shadow generation. This hinders Kyro2's scores in Giants for example. Im not sure, but 3DM2k1 could be using this for shadows also. This will be fixed in DX8.1.

3DM2k1

3DM2k1 is giving out generally poor results troughout the line. There are several reasons that hinder the score.
Possibly render to texture shadows. Game 2? DX8 bug forces them to be done in software
Lack of DXT3 texture compression (DXT1 only). Textures are run w/o compression. The 30% hit from trilinear filtering kicks in.
DOT3 bumpmaps. They seemed like poison to Kyro2. Game1 High detail uses this.
Exactly these (Game1 hi-detail and Game2) were pointed out as the Kyro2 weak points. Luckyly the DXT3 compression is only usefull for translucent textures and is not such a big flaw. If 3DM2k1 was able combine the use of compressed and uncompressed textures, it could help Kyro2's score plenty. Also, using EMBM bumpmaps (more popular anyway) would help and the DX8 bug will be fixed.
Also a visual anomality was detected in the hi-poly test, where some of the polygons were missing. This seems to me like a problem in the size of the displaylist. A driver issue. This anomality was recorded by only one reviewer.

anyways, Im recieving my Kyro2 today or monday. Ill be using it till there is a good price/perf DX8 part out.

P.S: Id be interested to see if anyone with a Kyro2 could do some benchin in 3DM2k1 set to Bilinear filtering?

WillysNut
08-17-01, 06:29 PM
Well, I gave it a shot but I'm having problems with the new Powerstrip 3.0beta. It won't let me disable bilinear filtering. "Force Trilinear Filtering" is checked and no matter what I try, I can't disable it.

I'm using the 4.12 drivers. I checked the properities and options of the card but there is no bilinear filtering option. I know there were a couple of tweak progies out there but everything I've found is in German.

I have a Hercules 4500 and I've been pretty happy w/ it but I really want to do the voltage mod so I can OC it. Just gotta build up the nerve and practice my soldering. :)

Da Whip
08-18-01, 10:30 AM
Try this Kyro 2 tweaker;

http://www.actiontrip.com/files/util/kyro2tweaker.phtml[/URL]

maha_x
08-21-01, 04:06 AM
Just got my Kyro yesterday. I ordered the Club3D's 64Mb Kyro2 card as it was 1/3 cheaper. I got it for some $150, where the Hercules was $180. This should give U some idea of Finnish taxing...

The first bad thing was that I realised I couldnt use Hercules's drivers, I have to use the Reference drivers from PowerVR. They dont contain any presets. Version is 1.0.7.114. Does anyone know what's the difference? With reference and Hercules's drv.

I only got time to try out Q3Ademo and Colin McRae 2. Q3a game me solid 85fps @ 10x7x32bpp and all visuals maxed out. Colin2 I didnt get to test that much, I noticed some odd jumps when the lensflare comes in to the view. Othervise it ran perfectly smooth @ 8x6x32, Trilinear, bump and details maxed out. As soon as I get the lensflare sorted out, Ill test more with higher resos...

dolemitecomputer
08-21-01, 10:33 AM
I just got a Hercules Kyro 2 and am pretty impressed. Decent frame rates and the environmental mapping even though it is not DOT3. I have been messing with the settings using the Kyro Tools XP program under windows 2000 and it still seems to get some type of flicker at times. Kind of like if you have VSync disabled. Seems to appear when using Quake 3 and I turn a corner quickly or move side to side quickly. It is not that obvious but noticable. Also the other thing is with the "space" CTF map. The one where you have two rotating portals that you jump though. The textures themselves seem to rotate very slowly compared to before. I guess my question what settings have you found that give you the best visuals?

maha_x
08-22-01, 01:47 AM
Umm, havent got much time to test out all settings etc. I'll have to get back to that...

Meanwhile, here's some very interesting reading (proving my point): http://www.xbitlabs.com/video/kyro2-2/

WillysNut
08-22-01, 10:12 AM
Originally posted by maha_x
Umm, havent got much time to test out all settings etc. I'll have to get back to that...

Meanwhile, here's some very interesting reading (proving my point): http://www.xbitlabs.com/video/kyro2-2/

I am getting ready to do this. A guy at work is great w/ a solder gun and he said he could do it w/o a problem. I'm a little nervous but I'm also jonesing to get some first-hand soldering experience so I'll keep you all posted on how everything works out.

I removed the tiny b-orb cooler from my chip and found that it was barely making contact originally. I bent the plate a little, added some AS2 and I can hit 186MHz stable now so I'm hopin' for 200MHz w/ the voltage mod and some cooling mods.

dolemitecomputer
08-22-01, 06:59 PM
Originally posted by maha_x
Umm, havent got much time to test out all settings etc. I'll have to get back to that...

Meanwhile, here's some very interesting reading (proving my point): http://www.xbitlabs.com/video/kyro2-2/

Now I know what is generating so much heat at the corner of the card. It is that voltage regulator......feel like I want to slap some arctic silver on it with a small section of a ram sink. :D