Erfaringer med å sette AGP aparture til 256?

[gamer73]

Ja..noen?

 

Det er jo normalt 128 i default. Men jeg fikk et tips in-game BF2 om å kjøre aparture på 256 siden skjermkortet mitt har denne mengden ram. Jeg kan vel egentlig si at jeg ikke merket noen særlig forkjell da, men det hakker litt i BF2 uansett pga noe jeg vil tro er bugs i spillet.

 

Noen som kan kommentere det? Hjelper det? cons and pros?

Endret 25. juni 2005 av gamer73

[shabador]

Vet ikke om dette er cons eller pros. Jeg ser på det som con. Her er en liten quote:

 

AGP Aperture Size is NOT how much RAM your AGP system uses. Effectively, ALL your RAM can be used for AGP. AGP Aperture size is exactly that, the aperture or “window” used for memory transfer. It’s a transfer buffer.

 

This is based on the amount of system RAM you got, vs. the amount of RAM your Video card has. Thus, if you got 1gig System and 256meg on the card, setting it at 64meg means the card can swap out 64meg from Video RAM to System RAM at one time.

 

Many of you are now thinking “Oh! let’s just set it to 256meg then so it can swap out the entire 256meg on the card!” Well… the problem is, the Aperture size is a transfer buffer. The bigger you make it, the less System RAM you have available. Thus, 256meg is using 256meg of System RAM as the transfer window… leaving you with 764 for textures and programs.

 

It’s a “best bang for the buck” setting, and rather than max it as recommended, I suggest you tweak it to find the best setting. 64meg really IS best for most modern cards and memory systems. 128meg may give a performance boost on systems with lots of RAM. 256meg is usually eating too much system RAM to be worthwhile.

 

In tweaking, I actually get best performance with 64meg. 128 gives 1-2 fps slower on UT2k4 and Doom3 timedemos and 256 gives 5-9 fps slower

Endret 25. juni 2005 av shabador

[Ozelot]

Dette skal prøves!

(både i BF2, og 3dmark)

[gamer73]

hmm ja kanskje ikke så lurt for meg å sette den til 256 allikevel da. Siden jeg bare har 1 gig med ram

[Frijazz]

hmm ja kanskje ikke så lurt for meg å sette den til 256 allikevel da. Siden jeg bare har 1 gig med ram

Prøv deg fram, gjør noen tester og se hva som passer deg best. Blant annet har 6800-serien hatt en tendens til å bli litt ustabile ved lav AGP aperture size.

Endret 25. juni 2005 av Frijazz

[Krezzo]

da har jeg lært meg noe nytt i dag også. helt fantastisk

[Scortech]

First of all, AGP Aperture memory will not be used until your video card's on-board memory is running low. That means it will usually not impact your gaming performance because developers are trying hard to not exceed the on-board memory limits.

The bigger your video memory, the smaller your Aperture Size could be. However with later games requiring more and more texture memory a good number seems to be 128MB Aperture Size for all cards with 64 MB to 256 MB Video RAM.

Setting the Aperture Size to HUGE values will not increase performance because this merely sets the maximum amount of physical memory that can be used. It only makes the GART Table bigger because every 4K page has its own entry, no matter if allocated or not.

Setting the Aperture Size to too small values could result in running out of available texture memory especially on a low-mem video card. It is also possible that developers make use of the GART's features by creating textures as 'non-local'.

 

If you experience in-game stuttering try playing with the size of your Aperture.

[Scortech]

Tror dette sier det meste

 

This BIOS feature allows you to select the size of the AGP aperture. The aperture is a portion of the PCI memory address range dedicated as graphics memory address space. Host cycles that hit the aperture range are forwarded to the AGP without need for translation. The aperture size also determines the maximum amount of system RAM that can be allocated to the graphics card for texture storage.

 

The AGP Aperture size can be set using the formula : maximum usable AGP memory size x 2 plus 12MB. That means that the actual usable AGP memory size is less than half of the AGP aperture size. That's because the system needs a write combined memory area equal to the amount of actual AGP memory (uncached) plus an additional 12MB for virtual addressing.

 

Note that all this is merely address space, not physical memory used. The physical memory is allocated and released as needed only when Direct3D makes a create non-local surface call. Win95 (with VGARTD.VXD) and later versions use a waterfall effect. Surfaces are created first in local memory. When that memory is full, surface creation spills over into AGP memory and then system memory. So, memory usage is automatically optimized for each application. AGP and system memory are not used unless absolutely necessary.

 

Now, many people recommend the AGP aperture size should be half of the amount of RAM your system has. However, that's wrong for the same reason why swapfile size shouldn't be 1/4 of the amount of RAM you have in your system. Like the swapfile's size, the required AGP aperture size will become smaller as the graphics card's memory increases in size. This is because most of the textures will be stored on the graphics card itself. So, graphics cards with 32MB of RAM or more will require a smaller AGP aperture than graphics cards with less RAM.

 

If your graphics card has very little graphics memory, then you should set the AGP aperture size as large as you can, up to half the system RAM. For cards with more graphics memory, you needn't set the aperture size to half the system RAM. Note that the size of the aperture does not correspond to performance so increasing it to gargantuan proportions will not improve performance.

 

Still, it's recommended that you keep the AGP aperture around 64MB to 128MB in size. Now, why is such a large aperture size recommended despite the fact that most graphics cards now come with large amounts of RAM? Shouldn't we just set it to the absolute minimum to save system RAM?

 

Well, in the first place, many graphics cards require an AGP aperture of at least 16MB in size to work properly. This is probably because the virtual addressing space is already 12MB in size! In addition, many software have AGP aperture size requirements which are mostly unspecified. Some games even use so much textures that AGP memory is needed even with graphics cards with lots of graphics memory.

 

And if you remember the formula above, the actual amount of AGP memory needed is more than double that of the required texture storage space. So, if 15MB of extra texture storage space is needed, then 42MB of system RAM is actually used. Therefore, it makes sense to set a large AGP aperture size in order to cater for every software requirement.

 

Note that reducing the AGP aperture size won't save you any RAM. Again, what setting the AGP aperture size does is limit the amount of RAM the AGP bus can appropriate when it needs to. It is not used unless absolutely necessary. So, setting a 64MB AGP aperture doesn't mean 64MB of your RAM will be used up as AGP memory. It will only limit the maximum amount that can be used by the AGP bus to 64MB (with a usable AGP memory size of only 26MB).

 

Now, while increasing the AGP aperture size beyond 128MB wouldn't really hurt performance, it would still be best to keep the aperture size to about 64MB-128MB so that the GART table won't become too large. As the amount of onboard RAM increases and texture compression becomes commonplace, there's less of a need for the AGP aperture size to increase beyond 64MB. So, it's recommended that you set the AGP Aperture Size to 64MB or at most, 128MB.

[gamer73]

JA! det sies alt! Jeg setter AGP'en tilbake til 128.

 

Takk for opplysende informasjon gutter!

[iStephano]

Så meg med 6800LE 128mb kan like godt ha den på 64MB siden da yter den best i følge teksten over her?

 

Jeg har 1Gbram på pc`en så hvis jeg øker den til 128mb har det ikke noe og si for den tar ikke så mye av rammen min for det?