Hi,
redrumloa wrote:
Oops sorry, fixed the link!
Umm.. Would you kindly run Karlos' pixeltest and tell me what your output bandwidth is? That's 68K.
Actually the output bandwidth is measuring conversion speed from one pixel format to another as that is what the program was written for - to help me optimise my low level pixel conversion routines (which convert between different chunky formats on the fly, in this case, direct to VRAM from RAM). That's why you see the conversion speed compared to simple copy speed. 100% implies the conversion is already faster than the bus can keep up with (ie as fast as just copying the data) and hence as optimal as can be hoped for.
However, if you don't specify a source format, that operation is a copy (hence it should be close to the copy speeds) anyway.
It works as a benchmark generally in that it tries to measure how fast your main memory and video memory is for "best case" accesses (long aligned 32-bit transfers).
For guestimating your bus performance you should look at
Read VRAM
Write VRAM
RAM -> VRAM (and the move16 version if you have 040/060)
VRAM -> RAM (and the move16 version if you have 040/060)
If the move16 versions score significantly higher on 040/060, you have a good bus design ;-)