AGP Aperture?

PowerMacG5

Diamond Member
Apr 14, 2002
7,701
0
0
Could someone explain what the AGP Aperture setting in the BIOS means? I am currently running the GeForce4 Ti4600, and was wondering what size it should be set to. The default value is 64 MB and it goes up to 256 MB on my motherboard.
 

Peter

Elite Member
Oct 15, 1999
9,640
1
0
In simple words, that's the maximum amount of system memory the graphics card may borrow when it runs out of its own.

Setting this to more than half of your total system memory doesn't make much sense, neither does keeping it too low.

All this doesn't matter much at all in real life, since whenever the graphics card can't fit a scene in its own memory, performance is going to suck no matter how much system memory it borrows - simply because of the huge speed difference from graphics card local memory to borrowed system memory accessed through AGP.

regards, Peter
 

Mem

Lifer
Apr 23, 2000
21,476
13
81
I never use more then 128mb ,infact using 64mb AGP size at the moment being it gives me the same performance as 128mb,and I`ve 512mb of main ram.
 

PowerMacG5

Diamond Member
Apr 14, 2002
7,701
0
0
I don't know if this makes any difference to your recommendations, but I have 640 MB of PC800 RDRAM. Do you think I should set the aperture higher than 128 MB because of this?
 

Mem

Lifer
Apr 23, 2000
21,476
13
81
but I have 640 MB of PC800 RDRAM. Do you think I should set the aperture higher than 128 MB because of this?

128MB should be fine ,however you can set it to 256mb if you want,it`s really down to you.
 

Instagib

Golden Member
Mar 9, 2002
1,344
0
0
Since you have so much system ram in doesnt make diff if you set it to 128 or 256.
 

PowerMacG5

Diamond Member
Apr 14, 2002
7,701
0
0
Thanks for all of your help. I'll set it to 256, and see if my gaming experiance has improved.
 

rimshaker

Senior member
Dec 7, 2001
722
0
0
I don't think you guys with 128mb video cards should worry too much about it, just set the aperature at 64mb minimum. I guess it's analagous to the swap file size debate. It's only used when main memory runs out, but if you got like 512mb and above... who cares, just pick a minimum.
 

BFG10K

Lifer
Aug 14, 2000
22,709
3,002
126
The AGP aperture size sets aside a linear portion of system memory that is directly mapped to the VRAM. Since reads/writes to this area don't require any address translation it's faster to utilise it than the rest of the system memory. Set it to 64 MB and increase it only if you're having problems as setting it too high can waste RAM.