Video RAM - how much do you really need? ;)

[Final8y]

This may surprise some of you .

What happens when you run out of RAM?

Contrary to popular belief, it's not the quite end of the world if your graphics card doesn't have enough onboard RAM to store everything. The drivers and hardware handle things quite nicely, and games can be programmed to ensure that the performance doesn't crash into the floor (especially those that constantly stream data out of system memory like Oblivion). The most common side-effect is something called "texture thrashing" - if there isn't enough onboard memory to store all of the textures needed, then some will remain in the system memory. When the graphics processor wants to use them, it copies them across into its RAM, deleting other stuff to make room. Cue a spot of stuttering or slow down in the frame rate; this is because it takes quite a bit longer to swap textures around than just accessing them in the onboard (or to give it the correct name, local) RAM.

Now see how much Vram is really used in games past & present with different levels of Res & AA.
http://www.yougamers.com/articles/13801_video_ram_-_how_much_do_you_really_need-page2/

If you're plumbing for the latest, hot-snotting 3D beast, with as much RAM as possible, be prepared to encounter some additional problems, if you don't have enough system and virtual RAM to back it up with. Without going into all of the gory details, one needs to remember that rendering data is copied across from the system memory, not "cut n pasted". So a game that's using 300MB of video memory, just for things like texture buffers, is going to take that slice out of your system memory too. For 32 bit operating systems, there's also a limit to how much virtual memory a game can have, and there are many cases where a graphics card using lots of VRAM can eat into this limit so much, that it causes the game to run badly and even crash. Sometimes this can be fixed with patches, but for real solution to this, for the future, is to have a 64 bit operating system.

Don't muck around with the Page File either.

 

[helmutcheese]

Nearly 700MB sucked up.

http://forums.overclockers.co.uk/showthread.php?t=17860000&highlight=768MB+username_helmutcheese

 

[HangTime]

Nice article.

The last quoted point is a good one; I remember when I was playing FEAR with only 1gig system RAM, I had to have Textures set to Medium even on a 512meg card because putting textures up to high increased my (system) RAM usage by around 300meg.

Interesting to see CoD4 using so much video memory (~400meg regardless of resolution) as I found it ran fairly smoothly on my 320meg card.

Looks like I'm justified in holding off playing the STALKER and CRYSIS games until I've upgraded though

 

[Final8y]

Nice article.

The last quoted point is a good one; I remember when I was playing FEAR with only 1gig system RAM, I had to have Textures set to Medium even on a 512meg card because putting textures up to high increased my (system) RAM usage by around 300meg.

Interesting to see CoD4 using so much video memory (~400meg regardless of resolution) as I found it ran fairly smoothly on my 320meg card.

Looks like I'm justified in holding off playing the STALKER and CRYSIS games until I've upgraded though

By the end of the year i would say 512MB will be the new realistic minimum with the avg enthusiasts screen res being 1680x1050 & 1920x1200.