Hardware Reference
In-Depth Information
Figure 12.2. Using GPU-Z to identify a GPU and its features.
Video RAM
Most discrete video adapters rely on their own onboard memory that they use to store video images
while processing them. Systems with integrated video use the universal memory architecture (UMA)
feature to share the main system memory. In any case, the memory on the video card or the memory
borrowed from the system performs the same tasks.
The amount of video memory determines the maximum screen resolution and color depth the device
can support, among other features. You often can select how much memory you want on a particular
video adapter; for example, cards with anywhere from 512MB to 4GB of video memory are common
choices today. Although having more video memory is not guaranteed to speed up your video adapter,
it can increase the speed if it enables a wider bus (for example, from 256 bits wide to 384 bits wide)
or provides nondisplay memory as a cache for commonly displayed objects. It also enables the card
to generate more colors and higher resolutions and allows 3D textures to be stored and processed on
the card, rather than in slower main memory.
Many types of memory have been used with video adapters. These memory types are summarized in
Table 12.6. Memory Types Used in Video Display Adapters
