A doubt

Last saturday I was discusing with a friend about video memory and on
board cards, and he insisted that it is better to have video memory in the
system ram instead of the video card itself because is faster to move
images from system memory than video memory. It is true?–
Roger D. Vargas | El sistema se apagara en 5 segundos.
ICQ: 117641572 | Salvese el que pueda!
Linux User: 180787 |

Can you be a little bit more precise in what you mean by “video memory”?
Usually that term referes to memory that is displayed on the screen by
the video hardware. This kind of memory is also known as the frame
buffer. This memory is usually on the video card, but it can be part of
main system memory that is shared by the video display and the CPU.
Sharing memory is common on low end PCs. Is that what you are talking
about?On the other hand, there is a very old debate over whether it is faster to build an image in main memory an copy it to the frame buffer or to build it in the frame buffer directly. In the bad old days of VGA cards it was usually faster to build an image in memory and copy it to the frame buffer. In the nice new days of accelerated graphics cards the answer depends on how much hardware acceleration you have available and how much your software can use. Generally if you have a lot of acceleration available in your graphics hardware and a library (like OpenGL or DirectX) that can use it then it is much much faster to do all your work in the framebuffer. So, the answer will always be “it depends.” Hope that answered your question Bob Pendleton “Roger D. Vargas” wrote:

Last saturday I was discusing with a friend about video memory and on
board cards, and he insisted that it is better to have video memory in the
system ram instead of the video card itself because is faster to move
images from system memory than video memory. It is true?


Roger D. Vargas | El sistema se apagara en 5 segundos.
ICQ: 117641572 | Salvese el que pueda!
Linux User: 180787 |


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I’ve noticed that if the video card is integrated with the northbridge
(like with the i810), you can reach some pretty fast speeds. It can do
this because it completely avoids the PCI and/or AGP buses that way.

However, this all depends on what kind of graphics you plan on doing.
If you’re planning on doing 3D graphics, I would imagine having
dedicated video memory would be better since it’s usually a few
nanoseconds faster than system memory. On the other hand, using system
memory for 2D graphics may be the best thing if you aren’t taking
advantage of hardware blits.

BryanOn Mon, Jan 07, 2002 at 02:52:48PM -0500, Roger D. Vargas wrote:

Last saturday I was discusing with a friend about video memory and on
board cards, and he insisted that it is better to have video memory in
the system ram instead of the video card itself because is faster to
move images from system memory than video memory. It is true?


http://www.bokeoa.com/ | @Bryan_Stillwell
GPG fingerprint: 33F7 44F2 8612 E02F 8DE8 97FB 621E 8A36 6DC1 32AF
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“Roger D. Vargas” wrote:

Last saturday I was discusing with a friend about video memory and on
board cards, and he insisted that it is better to have video memory in the
system ram instead of the video card itself because is faster to move
images from system memory than video memory. It is true?

No. Nor is it false. However, it’s offtopic.