Shared video memory

[wouldbewarrior]

I just bought a new laptop pc with 512mb of ram and "up to 64mb shared video memory through AGP 4x interface" however when I checked up on the current memory allocations through the directX diagnostic i was disappointed to find that only 32mb of ram were allocated to the shared memory cache (when checking the ram specs it stated 480mb available, which makes sense)... is there a way to change this allocation or did I get gipped? Any help would be greatly appreciated.

 

[pmonett]

The amount of shared memory used is a BIOS parameter called AGP Aperture Size, or something like that.
32MB is the default setting. You can probably set 16 to 64MB. All you should need to do is boot the laptop into the BIOS panel and hunt the Advanced tab for the above parameter. Change the value of the setting and you're done.

 

[cdogg]

pmonett,
Actually, the aperture setting is usually defaulted to 64MB and typically you don't want to change it. I don't think that is relative in this case anyway. Onboard video will use a portion of system RAM directly, ranging from 8MB to 64MB which is totally separate from the AGP Aperture.

wouldbewarrior,
I would go to Start -> Run, type dxdiag and hit OK. If you're running DirectX 6.0 or later, this will launch a diagnostic utility. On the Display tab it will tell you how much video memory your system is using.




~cdogg

"The secret to creativity is knowing how to hide your sources."
- A. Einstein

 

[pmonett]

Thanks for setting me straight cdogg. Yet, the AGP aperture size is a parameter that came at 32MB on several of my mainboards, and I had to change it to 128MB to alleviate certain issues with 3D Mark 2001.
Besides, certain video-intensive applications did benefit from the change also.

 

[cdogg]

Yes, you're absolutely right. In some cases, adjusting the AGP Aperture Size can help in some benchmarks. However, if you increase the aperture size too high (256MB for example), you can see a decrease in performance. The same can be true if you go below 32MB.

Bottom line: If you're not having any problems, it's best to leave it at the default.




~cdogg

"The secret to creativity is knowing how to hide your sources."
- A. Einstein

 

[pmonett]

I agree, 128MB seems to be the sweet spot. I'll leave it there as long as it works.

 

[MrTipster]

<b>The AGP aperature size is something completely different.</b>Even computers that do not have shared memory have this setting. This is usually best set at 100-200% of the actual ram of your graphics card. You need to go to bios and look at &quot;intergrated components&quot; and then adjust the shared memory to whatever ratio you like.

Some models of laptop can do it via a software program within windows but if not do it in the bios.

 

[cdogg]

This is usually best set at 100-200% of the actual ram of your graphics card

I disagree. First of all, you do not need to change this setting unless you are having problems. One example is a 4MB video card (yes, they used to exist). There's no setting for 8MB AGP Aperture on any motherboard that I've seen. Secondly, you NEVER want to go below 16MB for stability reasons. The AGP Aperture size is defaulted at 64 or 128MB for a reason. Very rarely do you need to decrease the size.

Also, if you increase the size beyond 128MB, you risk making the problem worse...

~cdogg

&quot;The secret to creativity is knowing how to hide your sources.&quot;
- A. Einstein

 

[Grenage]

Indeed, my card has 128mb and I find the appature size great set to 64mb.

Horses for courses