AGP Aperture Size in Bios

[mlbcujo27]

I was given some info on how to change this to make the game work better, but I don't know exactly how. So I am hoping someone can give me some directions as to getting to change this. I was told that you can change it when you restart your computer, but nothing worked there, so I don't really know where it is supposed to be changed.

 

[Zanmato]

Make sure your card uses the AGP first, if it's PCI it will make no difference.
Enter the BIOS setup when you boot up, usually hit the 'del' key. In most BIOS setup the AGP options will be under 'Advanced Chipset Features'. The default is 64mb, but it can be as low as 16mb or as high as 512mb depending on the BIOS version. I would only go as high as 128mb or 256mb, as the higher the aperture size, the more system RAM will be needed to table the graphics for the card.

 

[Akhenaton]

I was given some info on how to change this to make the game work better, but I don't know exactly how.

It's highly unlikely that your game will work "better" if you change this setting. Zanmato already pointed out how to do it, if you still want to experiment. Detailed instructions are found in your motherboard manual (or if it's a preassembled system, in the manual it came with or which can be obtained from the manufacturer's website).

What is the "best" setting depends on your graphics card and system RAM available. For most configurations, it doesn't matter at all (except that for certain special compatibility reasons, at least 16MB is recommended). More discussion here.

 

[filcivfan]

its advisable to use half of your existing vid card ie 256mb vid card set your aperture to 128 and so forth

 

[Akhenaton]

its advisable to use half of your existing vid card ie 256mb vid card set your aperture to 128 and so forth

Not it isn't. This is a popular misconception, or should I say urban legend. The more video RAM you have on the card, the less you need system RAM and hence even the possibility of accessing it through the MB supported direct method. There is zero benefit of enlarging the aperture for cards with large amount of video RAM. For example, with 512MB cards that would mean a 256MB aperture which will never be used for anything.

There are some claims that because the larger aperture will mean a larger GART table, traversing that table will be slower, but I haven't seen any actual science or even credible explanation to back that up. There is no independent latency adjustment and because the GART is arranged sequentially (to solve the very problem of fragmentation to the physical RAM), there should be no performance penalty in traversing it even if it was however large, because the empty part just won't be used. Obviously the table itself takes some memory of its own, but we are talking about minuscule amounts there (something like around 10 kilobytes per 256 megabytes of RAM, with the GATT and TLB included).

 

[Zanmato]

its advisable to use half of your existing vid card ie 256mb vid card set your aperture to 128 and so forth

For a 256mb card, the aperture size will make very little difference in performance if any. Increasing the size does make the GART table bigger but as Akhenation said it's tiny amounts of RAM. The card will not use the aperture until the video memory is running low anyway so a size of 128mb for the aperture should be more than enough for 128mb and 256mb cards nowadays.

However in earlier days of video cards graphics memory was rather limited and ran out quickly (a single 32-bit 512x512 MIP-mapped texture consumes ~1.5 MB) so AGP added a mechanism to use the system's main memory as additional storage for graphics data such as textures. This is what the AGP Aperture is. - from TechPowerUp website

 

[Mikesla]

Hi.

I own a Radeon 9550 vid mem 256.

I have mine set to 32 megs for apt size. I have seen differences in fps preformance on most of my games.

I also would like to mention that on some of these games I have had to lower my resolutions due to the video card cpu. As far as Civ 4 is concerned though, I can run this baby at the highest possible settings with no degradation in preformance.

I own Civ 4, BIA Earned in blood, call of duty 2, silent hunter III, among others. I tested each, and every game I have installed with each AGP setting from 4 to 256 megs. I have finally opted for 32 megs apt size. I have seen on most of my games real preformance hits at higher sizes such as 128, and 256, and at the lowest settings 4 megs, 8 megs, and 16 megs. I have also seen some marginal preformce results using the default (64 megs).

I started to take an interest in this AGP size because I could not grasp the reason why I would want it to be higher since my video card has well over enough texture memory.

Anyway, I haven't done any benchmark tests to backup what I have said, but to me it works fine.

As far as I am concerned I am very happy with what I have discovered.

It all comes down to is personal preformance, and what is acceptable for you.

Later!

 

[filcivfan]

lol well that was college days when we were still on amd k6's i sit corrected. though i agree it really doesnt matter that much