Question about EVGA GTX 680 graphics card

[RatB0Y68]

As the title suggests, I have a question about my graphics card.

 

It is an EVGA GTX 680 CLASSIFIED with 4GB VRAM (supposedly). However, after monitoring my GPU memory usage when playing skyrim using process explorer, I find that it hits approximately 95% usage at about 1.5GB VRAM, which would seem to suggest much lower VRAM capacity.

 

When I look up driver information the EVGA registers as an NVidia Geforce GTX 680, which as far as I know has 2GB VRAM.

 

I'm probably missing something obvious here, but if anyone learned with regard to GPUs could tell me what exactly is going on here I would be grateful, I can't help but feel that my GPU isn't what it is claimed to be.

 

Thank you for your time.

[FMod]

680 can have 2GB or 4GB (which is really a waste of money - 680 is bandwidth limited, not capacity limited - but a lot of people buy them anyway).

 

You can verify it using GPU-Z: http://techpowerup.com/gpuz/

Edited February 21, 2013 by FMod

[RatB0Y68]

What exactly do you mean by bandwidth limited? Also I used GPU-Z like you recommended, and it says the bandwidth is 192 GB/s. Does this mean that half of my GPU's VRAM is going to waste?

[FMod]

GPU-Z will tell you how much VRAM you have installed. Memory Size - 2048 MB or 4096 MB.

 

As to bandwidth, it's known that 680 scales strongly with memory clock. So it doesn't really use a lot of VRAM very well, at memory-intensive tasks where it might start running out, it slows down due to narrow bus. As a result there's usually almost no performance difference between 2048 and 4096 MB versions. It's not disabled or inaccessible, just not helping significantly.

Although if you're eventually going to sell it, both will hold their value.

[RatB0Y68]

That is unfortunate, it seems I would have been better off with the 2GB version. GPU-Z says I do actually have the 4096 MB version for all the good it does me.

 

I don't suppose there is anyway to compensate for or overcome this limitation? This is probably beyond my technical capabilities though.

 

Still, thank you for all your help, it is much appreciated.

[FMod]

I don't suppose there is anyway to compensate for or overcome this limitation? This is probably beyond my technical capabilities though.

No way. It was done as it was - 256-bit bus instead of 384 as usual - to save a dozen dollars on PCB layers. So the stock card only has 2GB for a reason.

 

Not like it hurts, though, just very few cases where it helps. In 3-way SLI on 3 displays, you'd definitely want 4GB (though there you'd want a 384-bit bus even more). Some of it will stay in resale value.

[Sartori75]

All I know is i bought the 670 2 gig and for the money really wish I had seen at the time the 4 gig option. I know this is not of help just ranting. :wallbash: