Question about performance

Xi0N · 2010-12-16 10:49:47

Well, i dont really know if this post could go here since it is a more hardware-specific question. If so, the mods can feel free to move it anywhere it should go in.

The thing is that my computer has 4 GB RAM. These 4 GB are reduced to 3.5 GB
This is because i have two graphic cards: One is integrated in the motherboard, and the other one is an external PCI-E one (Both nvidia)
I set a setting in the BIOS for something like "Hybrid SLI mode" which forces me to select an amount of RAM to be assigned to the cards teaming. This can go from 128 MB (If i remember properly) to 512 MB - I chose 512 Mb

The first question is: Is this correctly chosen?

The second thing is that the RAM i have is divied in two banks of 2 Gb each, but one is 667 Mhz and the other 800Mhz.... having both of them reduced to the lowest, which is 667 Mhz.

My second question is: Would it be better if i keep the 800 Mhz memory, even though my RAM amount woulb be reduced to 2 Gb or 1.5Gb with the setting i commented before?

The main use i give to the computer is HD movies playback via the PCI-express card.... via HDMI to a 32" screen.... so i think here the amount of memory in the video card would be more important than the amount of RAM memory, wouldn't it?

Well, any advice/recommendation you can give me would be really appreciated.

Thanks!

o1911 · 2010-12-16 16:09:59

Hi Xi0N,

When you say 4 GB is reduced to 3.5 GB, what exactly do you mean? All 4 GB of memory is addressable if you use a 64-bit (x86_84) kernel; are you using the i686 version? If you want to use it all, you should use the 64-bit version. I personally don't see the benefit to running a 32-bit system but perhaps you have your reasons.

As for as a "Hybrid SLI mode" goes, SLI is the proprietary nvidia method of using multiple GPUs for rendering graphics and such. I do not think this applies to an integrated chip on your motherboard and a dedicated video card. It is likely that this memory setting you have chosen has no effect on anything, but I can't be certain.

Obviously having two different speeds of RAM will bottleneck the faster one. It is up to you whether you need more memory or you would prefer a slight speed boost. Seeing as you're primarily watching movies I would suggest to keep both sticks, seeing as you would not notice a difference in most cases anyway.

Also, the amount of memory contained in the video card is not really important... this is used to store textures in OpenGL applications and such, and movies won't benefit from them as they are CPU/RAM bound (at least I think so, and VDPAU may be a different story again).

I hope that helps

Last edited by o1911 (2010-12-16 16:13:39)

jollysnowman · 2010-12-16 16:17:22

I don't really see a reason to reduce the amount of RAM you have, unless you're putting in another box.

And to clarify, SLI is two discrete nVidia cards working together. Hybrid SLI is combining an onboard nVidia graphics chip with a discrete one. http://www.nvidia.com/object/hybrid_sli.html

Xi0N · 2010-12-16 16:28:54

Thanks for the replies
Im using x86_64.
As jollysnowman, im using "Hybrid sli": Combining on-board graphic card with an external one, but this requires some amount of RAM to be done... that is why 512 Mb are taken away.
I actually do use vdpau for video playback: It really improves HD video playback....

Another thing i could do is stop using the internal video card, which would make me recover the 512 Mb of shared ram needed for "Hybrid SLI", and plug the 21" screen in the DVI output that the external card has but... will this decrease the performance of the HDMI output (plugged in the same PCI-express card)? - this is what i would be most afraid of.....

Last edited by Xi0N (2010-12-16 16:31:28)

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#1 2010-12-16 10:49:47

Question about performance

#2 2010-12-16 16:09:59

Re: Question about performance

#3 2010-12-16 16:17:22

Re: Question about performance

#4 2010-12-16 16:28:54

Re: Question about performance

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