AGP Aperture setting in Bios

[CorCentral]

I've read that you should set this to 256 for the newer cards, is this correct ? I have mine set at 64 & I have an EVGA 6800GT. What would I see different by changing this setting to 256 ? I have no problems running FarCry or Doom3 & they run as smooth as silk.


Here's a link that states the 256 setting :

3dGPU

 

[konakona]

i heard general rule of thumb is to set it at 1/2 of your available physical memory. i have radeon 8500 and set it at 256 since i got 512 total ram.

 

[pirred908]

If it ain't broke don't fix it.

 

[Navid]

Originally posted by: VanillaH
i heard general rule of thumb is to set it at 1/2 of your available physical memory. i have radeon 8500 and set it at 256 since i got 512 total ram.

I believe it is 1/2 of your graphics card memory (not your system memory). And even that is not something that everybody agrees with.
I have a 9600 pro (128MB) and have the aperture set to 64M.

 

[Gamingphreek]

Well there are 2 rules of thumb, 1/2 your main memory or equal to your video memory. Both of those ontradict certain key things.

To understand where to put it you first have to understand what it is. When a program uses memory they use the Video Cards memory or texture memory. On games like Doom III when there is not enough texture memory to go around you get a texture memory overflow and it has to find more. That "more" is AGP aperture almost like virtual memory only it is a lot slower than regular texture memory. So theoretically speaking as your video card memory goes up you AGP aperture should go down. However Doom III is said to require 512mb in some levels and the most we have is 256. So 256 is a safe bet but in normal games the odds that you will need more than the 128 Aperture are veyr slim. So if you are experiencing texture overflow, game slows down suddenly in huge environments with lots of textures and AA and AF then you might try giving more AGP aperture.

-Kevin

 

[Mareg]

Originally posted by: Navid

Originally posted by: VanillaH
i heard general rule of thumb is to set it at 1/2 of your available physical memory. i have radeon 8500 and set it at 256 since i got 512 total ram.

I believe it is 1/2 of your graphics card memory (not your system memory). And even that is not something that everybody agrees with.
I have a 9600 pro (128MB) and have the aperture set to 64M.

Yep, its 1/2 of gfx card memory. And I red a book about bioses that warned against setting agp aperture to high. Something about the memory index table taking to much place in the CPU memory buffer.

 

[guptasa1]

I get more and more confused all the time. LOL. Just last night I changed it from 256 to 64 because of this article (also tried 128):

http://www.rojakpot.com/default.aspx?location=7&var1=18

Didn't notice a performance loss or boost, but I really don't know WHAT to set it at. *sighs* LOL.

To quote this article (since the link doesn't take you straight to the page, and I hope quoting it's okay):

"AGP Aperture Size

Common Options : 4, 8, 16, 32, 64, 128, 256

Quick Review

This BIOS feature does two things. It selects the size of the AGP aperture and it determines the size of the GART (Graphics Address Relocation Table).

The aperture is a portion of the PCI memory address range that is dedicated for use as AGP memory address space while the GART is a translation table that translates AGP memory addresses into actual memory addresses which are often fragmented. The GART allows the graphics card to see the memory region available to it as a contiguous piece of memory range.

Host cycles that hit the aperture range are forwarded to the AGP bus without need for translation. The aperture size also determines the maximum amount of system memory that can be allocated to the AGP graphics card for texture storage.

Please note that the AGP aperture is merely address space, not actual physical memory in use. Although it is very common to hear people recommending that the AGP aperture size should be half the size of system memory, that is wrong!

The requirement for AGP memory space shrinks as the graphics card's local memory increases in size. This is because the graphics card will have more local memory to dedicate to texture storage. So, if you upgrade to a graphics card with more memory, you shouldn't be "deceived" into thinking that you will need even more AGP memory! On the contrary, a smaller AGP memory space will be required.

It is recommended that you keep the AGP aperture around 64MB to 128MB in size, even if your graphics card has a lot of onboard memory. This allows flexibility in the event that you actually need extra memory for texture storage. It will also keep the GART (Graphics Address Relocation Table) within a reasonable size."

 

[3chordcharlie]

Think of it a little like this: AGP aperture is to video memory what swap file is to main memory.

On a 1gig system, you could set it as high as you want (barring the issues about CPU use above?). If you're trying to get by on 'not enough' main memory, or if it's not a gaming machine, drop it right down to make sure your system has enough memory to avoid hitting the swap file.

 

[Gamingphreek]

Well contributing to my other post how i said generally speaking the more video memory you need the less AGP aperture you need. Well just to add on it should never be more than half your system memory because then you run out of system memory, and if you do 1 of 2 things could happen.

You could get a happy little screen call the BSOD. Or you could just hear the lovely little thing in your computer called a HDD working non stop because you are using virtual memory because you allocated too much of your main memory to texture.

-Kevin

 

[MattB]

This is a pretty big topic, and every year it seems to change on the answers given. However in my experience, 256MB aperture based on today's system setup is a good number to start with. Since AGP aperture size allocates the amount of physical ram when video ram runs out, and since the vast majority of gamers has 512MB of memory or more, it's safe to go with 256. Windows XP on average uses about 100 to 150MB of RAM, leaving enough room for 256MB to be allocated to the game you're playing in case it runs out of video memory. In most cases, people won't notice any difference in performance between 128 and 256.

There's really no right or wrong setting, it really depends on your system configuration, which has too many variables to take into account. If you experience stuttering, by all means try 128, but whatever you do, don't go below 32, as that effectively disables the AGP.

This is a lot like the CPU priority debate. Some people say it's good to give more priority to games, but the CPU ends up working more and physics/A.I. may not have enough juice to give a smooth experience. As with the above situation, it's a hit or miss thing, the best thing to do is experiment. That's part of tweaking. The guide I wrote is a start-off point, the rest is up to you to fine-tune it to your preference.

 

[PhoenixOrion]

Originally posted by: 3chordcharlie
Think of it a little like this: AGP aperture is to video memory what swap file is to main memory.

On a 1gig system, you could set it as high as you want (barring the issues about CPU use above?). If you're trying to get by on 'not enough' main memory, or if it's not a gaming machine, drop it right down to make sure your system has enough memory to avoid hitting the swap file.

 

[Schadenfroh]

64mb

 

[jim1976]

Originally posted by: PhoenixOrion

Originally posted by: 3chordcharlie
Think of it a little like this: AGP aperture is to video memory what swap file is to main memory.

On a 1gig system, you could set it as high as you want (barring the issues about CPU use above?). If you're trying to get by on 'not enough' main memory, or if it's not a gaming machine, drop it right down to make sure your system has enough memory to avoid hitting the swap file.

Agreed except one thing. Being addressed as AGP mem doesn't mean that it's not used as system ram anymore. If nessecary system uses it.

 

[Schadenfroh]

Originally posted by: jim1976

Originally posted by: PhoenixOrion

Originally posted by: 3chordcharlie
Think of it a little like this: AGP aperture is to video memory what swap file is to main memory.

On a 1gig system, you could set it as high as you want (barring the issues about CPU use above?). If you're trying to get by on 'not enough' main memory, or if it's not a gaming machine, drop it right down to make sure your system has enough memory to avoid hitting the swap file.

Agreed except one thing. Being addressed as AGP mem doesn't mean that it's not used as system ram anymore. If nessecary system uses it.

does this apply on the nforce2 ultra 400 IE a7n8x deluxe? i could set the thing to 512mb and my system will use the ram if needed and not slow me down?

 

[jim1976]

Originally posted by: Schadenfroh

Originally posted by: jim1976

Originally posted by: PhoenixOrion

Originally posted by: 3chordcharlie
Think of it a little like this: AGP aperture is to video memory what swap file is to main memory.

On a 1gig system, you could set it as high as you want (barring the issues about CPU use above?). If you're trying to get by on 'not enough' main memory, or if it's not a gaming machine, drop it right down to make sure your system has enough memory to avoid hitting the swap file.

Agreed except one thing. Being addressed as AGP mem doesn't mean that it's not used as system ram anymore. If nessecary system uses it.

does this apply on the nforce2 ultra 400 IE a7n8x deluxe? i could set the thing to 512mb and my system will use the ram if needed and not slow me down?

It generally applies to all mobos. I'm not aware of an exception...

 

[3chordcharlie]

Thanks for the clarification - why not just set the aperture to the full system memory then? I've always used a ground-rule of 1/4 of my system memory, but I was under the impresion it was lost for system use, so my rule is out the window

 

[PhoenixOrion]

Originally posted by: 3chordcharlie
Thanks for the clarification - why not just set the aperture to the full system memory then? I've always used a ground-rule of 1/4 of my system memory, but I was under the impresion it was lost for system use, so my rule is out the window

You can if your mobo has that option. The only "must" rule is no less than 32MB.

If graphics app actually uses gfx onboard plus entire system memory (if there is any app like that), system will slow down because of numerous swapping/paging requests to hd. --> defeats purpose of physical system memory for app use.

 

[BFG10K]

Leave it at 64/128 MB unless you have problems.

 

[mb]

My laptop came with a 32mb video card and 512mb ram, and the factory setting for AGP aperture is 256mb

 

[JBT]

I have the answer for you guys instead of reading these stupid reviews on it that are completely BS anyways why don't you try benching it your self? The only time I have ever needed to up my aperture size was to run the Ruby demo with my old 9500 Pro. Other than that I have never noticed a difference. I had to set it to 256 to even get it to run decently.