 <p>The dynamic and staging are both likely to be in system memory, but their is good chance that your issue, is write combined memory. It is a cache mode where single writes are coalesced together, but if you attempt to read, because it is un-cached, each load pay the price of a full memory access. You even have to be very careful, because a c++ <code>*data=something;</code> may sometime also leads to unwanted reads.</p> <p>There is nothing wrong with a dynamic texture, the GPU can read system memory, but you need to be careful, create a few of them, and cycle each frame with a map_nooverwrite, to inhibit the costly driver buffer renaming of the discard. Of course, never do a map in read and write, only write, or you will introduce gpu/cpu sync and kill the parallelism.</p> <p>Last, if you want a persistent surface and only a few putpixel a frame (or even a lot of them), i would go with an unordered access view and a compute shader that consume a buffer of pixel position with colors to update. That buffer would be a dynamic buffer with nooverwrite mapping, once again. With that solution, the main surface will reside in video memory.</p> <p>On a personal note, i would not even bother to teach cpu surface manipulation, this is almost always a bad practice and a performance killer, and not the way to go in a modern gpu architecture. This was not a fundamental graphic concept a decade ago already.</p>