"AGP Aperture Size"?

[Mr. Cold]

What does the AGP Aperture Size setting do in the Abit BP6 bios for the G400 MAX?

What should it be set to, and why?

[Helevitia]

I haven't seen anyone give a real good answer to this question, but if you are using TurboGL you NEED to set it to 256MB. Why? I don't know but that's what the release notes say

Dave

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I can never think of a good signature...~

[Mark F]

First try 1/2 your memory.
Then try 256.
Then try your cards memory setting (MAX is 32).

Test each and use the one that works best for you.

Don't wory about the warning for TGL. If your MoBo is 'built right' 1/2 memory will work fine. Many don't so you need to set AGP to 256 to get good performance.

Experament to find your best settings.

Mark F

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OH NO, my retractable cup holder swallowed a DVD...
and burped out a movie

[Marcelo]

go to tweak3d.net and look for articles on G400, and they tell you what's good AGP Aperture size to set at, but I think it is good to try which one suit you best.

[Maggi]

The Graphics Aperture Size (GAS) determines the amount of your system RAM that can be used by your gfx card as texture memory.

DirectX seems to be able to map half the amount of your GAS, i.e. you set it to 256MB and gain 128MB of texture memory.

You could also set it to twice the amount of your actual system RAM to make all of your RAM available for AGP texturing. I once did so when having 'only' 128MB installed I set it to 256MB and all according tools reported a total of ~130`MB texture memory (rest of local gfx RAM plus available free system RAM).

...

I hope this answer is also good eonough your you, Dave ...


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Cheers,
Maggi

Despite my nickname causing confusion, I am not female ...

[Gurm]

Maggi's half right. It's not dependent on DirectX, though - it's dependent on your particular motherboard's implementation of AGP Aperture. Most (I'd say 90+%) new motherboards DON'T get this feature right, for some unknown reason. It's only been like 3 years since it was introduced, right? *sigh*

Anyway, I've always been lucky, because my ABIT BX6, BX6v2, BF6, and now ASUS P3B-F have always worked just fine at the correct setting, which is half of my system RAM.

- Gurm

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Listen up, you primitive screwheads! See this? This is my BOOMSTICK! Etc. etc.

[Rik]

Go for the lowest AGP aperture size you can get away with (within reason).
I've noticed that the greater your aperture size, the more system memory is lost at windows startup (about 1mb per 32mb of AGP aperture), before anything is even using AGP texturing.
I have found a 32mb aperture size to be optimal for me, with no adverse effects to performance or stablility.
AGP is overrated (and quite possibly evil) and will always be slower than textures held purely in video ram.

[Rampage]

I just want to know where I go to change my AGP Aperture size because I can't find it under the system's bios settings?

[Gurm]

Rampage,

Two possibilities...

1. You need a new BIOS to be able to change that setting. Check your Mobo maker's website.

2. Your mobo won't let you change that setting. In this case, a new mobo is only warranted if you are having problems.

- Gurm

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Listen up, you primitive screwheads! See this? This is my BOOMSTICK! Etc. etc.

[Chucky Cheese]

Gurm

i have a question that i think relates to agp systems. how does GART(..graphical address remapping table) play into all this? my system is a gx chipset, dual pIII based mobo and has 512 mb of pc100 ram.

if i set my agp aperture size to 256 my system becomes noticibly slower. it still is usable but it just isn't as fast as when it is set to 128 mb.

i do believe that it is an architecture attribute(..or anomaly) of any given design. my bios has some options that relate to agp;

1) agp multi-trans timer 32.....224
2) agp low priority 32.....224

both can be disabled and i have both set to their "optimal" settings, if i deviate i can see the difference on the desktop(win2k). i don't fully understand the function of those two bios options and was hoping that you might know.

chucky

[Gurm]

Since your board uses a server-based chipset, you are going to have a lot more options than the rest of us. I don't know specifically what those options do, but I'm guessing "optimal" is a pretty good place for them. You can probably turn down the priority of the AGP slot for server reasons - to give more priority to the SCSI or whatever instead, if it's a non-interactive server.

- Gurm

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Listen up, you primitive screwheads! See this? This is my BOOMSTICK! Etc. etc.

[Pace]

What chipset have you got Chucky Cheese?

Also, Rik, AGP will indeed be slower than textures held purely in local memory but watching the 3DMark99 texture rendering speed benchmark run at 3fps with Agp off and 40fps with it on I'd consider it benificial - plus new games will have more textures than can fit in my 8mb's of SGRAM - Agp will be and is essential then.

Plus the bandwidth benefits for geometry transferring can't be ignored.

Paul.

[Chucky Cheese]

Pace,

i have the 443GX xeon chipset, the board is made by american megatrends...you know, the bios people! they tend to be overpriced and they don't turn the highest framerate in gaming, however they are a very stable board...very well constructed. i've built 4 systems with their server boards in different hardware configurations with little to none compatability problems.

i like to play games(fps particularly) but i need the stability for autocad. when i built this one it was with win2k in mind. i've been wanting to get away from regular windows and win2k didn't let me down!

chucky

[Pace]

Sorry, didn't notice you had already mentioned GX in your previous post.

However, I take it that American Megatrends' manuals are as helpful as my SuperMicro one - e.g. "Display Mode at Add-On ROM Init
The settings for this option are Force BIOS or Keep Current."
I know the options I want to know what they do?!

Try emailing them though - SM seem to be quite good at answering all queries - they even sent me exact model numbers of every stick of RAM they had tested with their 8X0 boards - all I wanted to know was what speed of RAM I required for certain bus speeds - PC800 etc.

Paul