Sign in to follow this  
Guest freequest

TEXTURE_MULT_BANDWIDTH - I'd like to know more

Recommended Posts

This parameter in the fs9.cfg interests me. I have two copies of FS9 (both identical retail). One is on my gaming rig which uses a Ti 4200. The second copy is on my development machine which uses a TNT Vanta card, some 4 years old.The default installation on each machine reveals the following values for this parameter:1. Machine with Ti 4200:TEXTURE_MULT_BANDWIDTH=402. Machine with TNT Vanta:TEXTURE_MULT_BANDWIDTH= 30These values are closer to each other than I would have thought. If one assumes this parameter is there to make the most efficient use of the video cards texture bandwidth, then I wonder how the algorythm within FS9 decides what the value actually is? The bandwidth of my Ti 4200 is qouted by Nividia as being 8.0 Gb per second, whereas my TNT Vanta card is quoted by the same source as being only 1 Gb per second. So my Ti 4200 has eight times the bandwidth, but the TEXTURE_MULT_BANDWIDTH value is only 33% higher. So either the parameter does not relate to that particular video card specification, or there is some very non-linear algorythm that decides what the value should be. Whatever it is, and whatever it precisely means, the value appears to be generated from with Fs9 itself - this information is not in the display.cfg file.I'm curious as to what value this parameter is set to on your machine (with the value as set by fs9 - not manually adjusted), and what type of graphics card you use? It also seems to me that if my TNT Vanta scores a "30", then my Ti 4200 should score much higher than a "40", but unless I know how FS9 calculates the value, it's all speculation.

Share this post


Link to post
Share on other sites
Help AVSIM continue to serve you!
Please donate today!

I doubt it has anything to do with the actual memory bandwidth of the videocards. The memory bandwidth of the card is supposed to be completely transparent to the game as well as to the developer. The developers should not take into account the exact specifications of each and every videocard and write those values into a cfg file. Some cards may require special treatment for various reasons, to work around certain bugs or hardware limitations, but to determine the memoery bandwidth of each card and put it in cfg file does not seem reasonable at all to me. The variable probalbly controls something else.

Share this post


Link to post
Share on other sites

I'm inclined to agree. What it actually does, though, is still a bit of a mystery. I've been playing extensively with the value tonight to see if I could notice any difference. To be honest I couldn't notice anything different at all, regardless of the value I set - so I'm happy to leave it 40.

Share this post


Link to post
Share on other sites

Thanks for the link Don. It's interesting some people are noticing an improvement. As it I've been quite impressed by the speed of texture and scenery updating in FS2004 compared to FS2002. Maybe a lot of the improvements come down to individual machine specifications and user's individual settings.

Share this post


Link to post
Share on other sites

Well, I set mine to 400 -- no more blurry textures when I fly over them! The only minor texture problems remaining is a bit of flashing grey when switching views and it hasn't got the textures cashed yet, but then they load very quickly.Of course, I expected a heavy fps hit, but was extremely surprised how well FS worked with that setting, albeit with 2D panel and no wider than 75% zoom. I'm getting an average of 21-22 fps (locked at 24) with a Ti4200 and XP 1600 cpu. I think the trade-off is sharp textures vs. smoothness, in steep banks fps do vary more than before but overall average fps seems to be only ~0.6 lower than before while the visual quality is a lot better.Anyway, I have to do some more testing, I'm wondering if there's a difference between say 200 and 400 (perhaps the setting has a max value?). Overall, it looks better and is still very flyable -- I like hand-flying GA aircraft, so smoothness is important. Maybe, there's even a better compromise between smoothness and visual quality.

Share this post


Link to post
Share on other sites

Please let us know how your testing goes. Come to think of it, that flashing grey you are talking about - I noticed that as well, and on reflection it was when I set the value higher (I maxed it out at 240). Not sure if I noticed it at 100 though - I don't think I did. This is all on the Ti 4200 machine, btw.

Share this post


Link to post
Share on other sites

Mine is...TEXTURE_BANDWIDTH_MULT=60...on a Radeon 9800pro 128MBWhy does everybody else quote "TEXTURE_MULT_BANDWIDTH"...? ;)

Share this post


Link to post
Share on other sites

>Mine is...>>TEXTURE_BANDWIDTH_MULT=60>>...on a Radeon 9800pro 128MB>>Why does everybody else quote "TEXTURE_MULT_BANDWIDTH"...? ;)Oops. At least everyone knows what I meant. If your 9800 Pro is on 60, I'd most certainly better leave mine on 40.

Share this post


Link to post
Share on other sites

>Well, I set mine to 400 -- no more blurry textures when I fly>over them! The only minor texture problems remaining is a bit>of flashing grey when switching views and it hasn't got the>textures cashed yet, but then they load very quickly.>>Of course, I expected a heavy fps hit, but was extremely>surprised how well FS worked with that setting, albeit with 2D>panel and no wider than 75% zoom. I'm getting an average of>21-22 fps (locked at 24) with a Ti4200 and XP 1600 cpu. I>think the trade-off is sharp textures vs. smoothness, in steep>banks fps do vary more than before but overall average fps>seems to be only ~0.6 lower than before while the visual>quality is a lot better.>>Anyway, I have to do some more testing, I'm wondering if>there's a difference between say 200 and 400 (perhaps the>setting has a max value?). Overall, it looks better and is>still very flyable -- I like hand-flying GA aircraft, so>smoothness is important. Maybe, there's even a better>compromise between smoothness and visual quality.>>Yes I set mine the same as yours, with the UK VFR scenery the textures pop back into focus very quick after loading, and the blurries do not happen that often.Anthony

Share this post


Link to post
Share on other sites

According the the FAQ, that value is suppose to give priority to texture draw if you have at least a 128mb video card; but set to high can cause stutters like in FS2000. I upped mine to 400 with my 9700 Pro and noticed immediately how quick the texture draw was; but also noticed some minor stuttering when turning. I'm at =100 right now and seems to work good. Still fiddling with it though. I'll probably go to =200 and see what's up.

Share this post


Link to post
Share on other sites

Well my card is a old gf2 mx-400 I did adjust that setting and it appeared to make the sim run smoother but appearnces can be deceiveing* well ill just keep testing it out its no biggie.BTW my TEXTURE_MULTI_BANDWIDTH is 40 I figured it would be less o well.Out

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this