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Should I get 1 MB or 2 MB of video memory?
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Are the acronyms confusing? try the Glossary of computer terms |
For chipset information, go Here
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To determine the amount of video RAM you will need, use the method
outlined in "How do I calculate how much VRAM/DRAM I need?"
There is another issue which is important to consider if the video
card in question is a 64 bit card or is 32 bit but uses memory
interleaving. Standard DRAM is addressed 32 bits at a time and
typically one 1 MB bank is 32 bits wide and 256 kbytes deep, so
if 2 1 MB banks are installed, each can be addressed separately.
In practice, a 64 bit video controller can move 64 bits in or out
of video RAM in each clock cycle, 32 bits to/from each bank. If
only one bank of DRAM is installed (i.e. 1 MB) then the effective
bandwidth of the card is halved. In a similar fashion, a 32 bit
controller that supports memory interleaving like the ET4000W32i/p
can move twice as much data per clock cycle if it has 2 MB of DRAM
installed (see "How does memory interleaving work to increase
the speed of a video card?" This means that 64 bit cards that
have only 1 MB of video RAM will operate much more slowly that if
a full 2 MB is installed. This may result in lower refresh rates
and more sluggish performance.
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