VRAM: allocation vs actual real usage

[eHammer]

Hello,

I read an insightful post stating that even though some AAA games are 'allocating' HUGE amounts of Vram (6-8gb or more) these games aren't actually 'actively' using that much Vram.

So, that game would run the same on 3gb-4gb Vram as it would on 8gb+.
This is specific to 1080p gaming, not higher resolutions.

How accurate is this ???

Thanks for your help.

 

[TMTOWTSAC]

It depends on the game. Some games use ultra high quality textures and need every scrap of VRAM they can get. Others only need a little, but they can use the extra to cache currently unused data so levels will load faster.

 

[dontlistentome]

I think it's accurate. If you equate 'allocating' with 'recommended' and 'actively using' with 'required minimum' you see how this is. A game may require 4gb vram at minimum if you want to run at ultra settings, but have an 8gb card as recommended. So as long as you have 'enough', which in this example is 4gb, then the game will run the same. The extra ram may get allocated to be used for various reasons, but since it's not required it doesn't hurt performance if you don't have it.

 

[TMTOWTSAC]

AA levels also dramatically affect VRAM requirements. That's another reason for recommended vs minimum.

 

[bystander]

There have been tests with 2Gb and 4Gb versions of the same card, that show this in effect. While the 4Gb version was using more than 2Gb of VRAM, they performed equally in the benchmarks. This goes to show that the extra allocated VRAM just was not necessary. From a programming point of view, there is no point in releasing memory when you can keep different game data in the VRAM, even if it isn't needed just then.

 

[BFG-9000]

VRAM is frequently used to preload and hold compressed textures, which are generally only decompressed once in the texture units. They could just as easily be stored in System RAM at a slight increase in level loading time (like when entering a new room) and in fact are if the game engine determines you don't have enough spare VRAM. Such a thing would never show up in benchmarks measuring FPS.

Note that some very high game settings actually switch to uncompressed textures which of course would require even more VRAM not "actively" being used by the game.

 

[eHammer]

Thanks for the good info everyone.
Helped me make a good buying decision, bought a GTX 1060 3gb over a RX 480 4gb.

 

[mlga91]

Thanks for the good info everyone.
Helped me make a good buying decision, bought a GTX 1060 3gb over a RX 480 4gb.

I wouldn't call that a good decision.

 

[TMTOWTSAC]

The 1060 3 GB doesn't just have less VRAM, it's also a cut down version of the card with fewer CUDA cores and texture mapping units. The 480 4 GB and 8 GB are identical except for the VRAM. And lately, it's been on sale all the way down into the $150 range.

 

[eHammer]

Thanks for the good info everyone.
Helped me make a good buying decision, bought a GTX 1060 3gb over a RX 480 4gb.

I wouldn't call that a good decision.

AT THE PRICE I PAID FOR IT = YES IT WAS !!!
CPU Master ???? lol

 

[eHammer]

The 1060 3 GB doesn't just have less VRAM, it's also a cut down version of the card with fewer CUDA cores and texture mapping units. The 480 4 GB and 8 GB are identical except for the VRAM. And lately, it's been on sale all the way down into the $150 range.

I am not in USA, I am in Australia, and the price I paid for the card I bought was a bargain !!!! and the difference in performance between 3gb vs 6gb is what 5%-8% ???? is that worth an extra $100 YES OR NO ???

 

[eHammer]

Mods please close this thread.

 

[TMTOWTSAC]

Congrats then, as that guy at PC world likes to say, there are no bad video cards, only video cards with bad prices. And import taxes. And that batch from EVGA that was catching on fire...But yeah, AMD and Nvidia prices are wildly inconsistent from country to country.