How much graphic memory makes sense?
How much memory needs a video card and how much graphic memory is useful for specific application purposes?
Shared Memory / Onboard Graphic Cards
- Onboard video cards like GMA 950 are sufficient for office, internet and image editing.
For graphically not demanding jobs like internet surfing, office, image editing (e.g. with Photoshop), 2D games and some elder 3D games an onboard graphic card (a video card without own memory like e.g. Intel GMA 4500M or ATI Radeon HD 3200) is clearly sufficient and now remarkable speed losses can be measured compared with graphic cards with own memory. However, a fast RAM (Dual Channel) is recommended, because the graphic card uses parts of the RAM.
TIP: Caution with denominations like TurboCache (NVIDIA) and HyperMemory (ATI). They also indicate dynamically from RAM reserved memory. He is used additionally to the graphic memory, but clearly slower than the integrated memory. Also cards without these techniques can use additional memory from RAM, but this is even solwer than with TurboCache and HyperMemory.
64 MB, 128 MB, 256 MB, 512 MB or 1024 MB?
- Weaker graphic cards like ATI Mobility Radeon X1300 hardly benefit from more than 128 MB graphic memory.
- NVIDIA GeForce Go 7950 can benefit slightly with highest settings with antialiasing easily from 512 MB (compared to 256 MB).
If you want to execute graphically more demanding applications (3D) and 3D games, you often need faster graphic cards than current onboard models (see our comparison of graphic cards). How much memory is necessary and useful for such applications?
Basically, a lack of memory only slows down, when it is needed (that means, when the settings of resolution, texture details, anti aliasing or anisotrope filtering needs more memory than available).
Up to 256 MB graphic memory
Most old games up to 2007 need 128 MB with a resolution of 1024x768 pixels and without anti aliasing / anisotrope filtering. Entry level GPUs (like the 9300M GS) dont need more graphics memory than 256 MB, as the performance of the chip is not good enough to allow high detail settings.
512 MB graphic memory
Fast graphic cards (9800M GT and up) do profit from 512 MB graphics memory. Slower cards, like the 4670 or GT 240M dont profit much from 1024 MB. Its better to choose fast 512 MB GDDR3 instead of slow 1024 MB DDR3 graphics memory (if you have the choice).
1024 MB and up
Currently 1024 MB and more graphics RAM only makes sense for high end cards (like the GeForce GTX 280M) unsing high resolutions and Antialiasing. For SLI or Crossfire combinations, you have to count the amount of RAM each card has (and not sum it up as both cards store the same things in their memory).
Conclusion
Depending on video card and application purpose the size of graphic card memory differs. For office, internet and image editing models without own graphic memory (onboard chips) are sufficient. For current (2009) games without antialiasing 256 - 512 MB are sufficient. Only high end graphic cards compined with newest games, highest resolutions and antialiasing need 1024 MB.
Nonetheless the requirements are increased with every new generation of games ...
