Shared Video Memory and Memory Bandiwidth Issues? 37
klystron2 asks: "Does shared video memory consume a huge amount of memory bandwidth? We all seem to know that a notebook computer with shared video/main memory will have performance drawbacks.... But what exactly are they? It's easy to see that the amount of main memory decreases a little bit, but that shouldn't make a big difference if you have 1GB of RAM. Does the video card trace through memory every time the screen is refreshed? Therefore consuming a ton of memory bandwidth? If this is the case then the higher the resolution and the higher the refresh rate, the lower the performance of the system, right? I have searched the Internet for an explanation on shared memory and have come up empty. Can anyone explain this?"
Tom's Hardware have an article about that. (Score:3, Insightful)
Funny I was just reading an article [tomshardware.com] over on Tom's Hardware guide [tomshardware.com] about that
The article benchmarks three different boards with integrated graphics solutions (Intel i865G , nForce2, & SIS 651) using both the integrated graphics hardware, and a $50 graphics card.
Unsurprisingly, in 3D applications, all have quite poor performance [tomshardware.com], only the nForce 2 system has acceptable performance with even older games at low resolution.
More important to your question, They also run comparative benchmarks using windows office applications [tomshardware.com], with both the integrated graphics, and the $50 card. The graphs clearly show, that there is no effective difference in performance, and that the benchmark results are largely CPU bound.
In concussion, I would not expect integrated graphics to hut general computing performance. Though I would of course check that the graphics performance is adequate, as it may not be possible to update in the future.