highgrade
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VGA RAM
what is the difference detween 4mb vga & 8 mb vga card?
How to find out how much vram is reqd for your system?
How to find out how much vram is reqd for your system?
ASKER
In which manner 8mb vram is better than 4mb.?
First, terminology. VRAM is NOT synonymous with "RAM on video card". Differences will be explained later.
Second, in the 2D only days, the difference between 4 mb and 8mb card is the frame buffer size, which in turn determines the maximum resolution and color capability. The more memory, the higher resolutions and/or more colors capable.
Third, in the 2D/3D days (i.e. now), the onboard memory can be used for frame buffer (as above), OR as texture memory (store the textures needed for the 3D objects). The first Voodoo had 4 megs, 2 for each. Then some of the "better" ones had 4 meg textures and 2 meg frame buffer (Pure3D, for example). Voodoo 2 has 8 and 12 meg versions (4 meg frame, 4 or 8 meg texture mem).
So your question can be essentially answered as "depends on the video card. If it's a 2D card, more colors/higher res. If it's a 3D card, more texture memory".
(VRAM is a type of DRAM that can be both written to and read from in the same clock cycle, instead of requiring separate clock cycles)
Second, in the 2D only days, the difference between 4 mb and 8mb card is the frame buffer size, which in turn determines the maximum resolution and color capability. The more memory, the higher resolutions and/or more colors capable.
Third, in the 2D/3D days (i.e. now), the onboard memory can be used for frame buffer (as above), OR as texture memory (store the textures needed for the 3D objects). The first Voodoo had 4 megs, 2 for each. Then some of the "better" ones had 4 meg textures and 2 meg frame buffer (Pure3D, for example). Voodoo 2 has 8 and 12 meg versions (4 meg frame, 4 or 8 meg texture mem).
So your question can be essentially answered as "depends on the video card. If it's a 2D card, more colors/higher res. If it's a 3D card, more texture memory".
(VRAM is a type of DRAM that can be both written to and read from in the same clock cycle, instead of requiring separate clock cycles)
Good answer kschang.
kschang is the man!!! I reckon the points are his!
So does that answer your question, highgrade?
It's the only answer, give kschang his points........
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ASKER
how do i test how much memory is used by 2d & howmuch by 3d?
Depends on the chipset. On the Riva cards (TNT, 128, TNT2, etc.), a single bank of memory serves both. So does Voodoo 3. Voodoo 2 have separate frame buffers and texture buffers (different on the 8 and 12 meg versions), so there's really no way to tell. Is there any reason you need to know exactly?
ASKER
I have tried SIS 6326 based 4mb & 8mb card & could not find any difference in 2d/3d performance.
So i want to run some diags. or benchmarking test.
So i want to run some diags. or benchmarking test.
ASKER