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
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 900 / 950 or ATI Radeon Xpress 1150) 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.
32 MB, 64 MB, 128 MB, 256 MB o 512 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 128 MB graphic memory
Most current games (10/2006) need 128 MB with a resolution of 1024x768 pixels and without anti aliasing / anisotrope filtering. If graphic cards are used, whose performance is not able to represent these resolutions with high details, 128 MB are too much and unnecessary. So, video cards below the performance of a NVIDIA GeForce Go 7600 or ATI Mobility Radeon X1600 don't need more memory than 128 MB.
256 MB graphic memory
256 MB video memory are sufficient for almost all current games with high settings and a resolution of 1024x768 or similar. An improved performance with 256 MB only is possible with video cards of the mid range or high end class like NVIDIA GeForce Go 7600 or ATI Mobility Radeon X1600.
512 MB graphic memory
At moment, only few games benefit from 512 MG graphic memory (for large texture maps). Examples are Doom 3 and Call of Duty 2. Other current games gain an increase of 10% performance with 512 MG graphic memory with a resolution of 1280 x 960 pixels and quadrupled antialiasing. Nevertheless this affects only high end video cards like NVIDIA Geforce Go 7900 GTX or the new 7950 GTX.
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 games without antialiasing 128 - 256 MB are sufficient. Only high end graphic cards compined with newest games, highest resolutions and antialiasing need 512 MB.
Nonetheless the requirements are increased with every new generation of games ...



