In benchmarking 2D graphics accelerators, we've found that
the ability to quickly copy data from the host processor to the screen is
a critical operation. Many benchmarks focus on testing all kinds of BLTs
and ROPs and other specialized graphics operations. While these are
important, actual Windows applications perform a lot of host to screen
transfers.
We wrote two simple benchmarks that you can download in the in the phostone.zip
(500KB) file - PhotoStones and Cascade.
PhotoStones simply copies multiple true-color images from system
memory to the screen. It measures the number of pixels-per-second that the
system is achieving. From past experience, ISA bus computers will achieve
about 1 MPix/sec, EISA about 2 MPix/sec, VL-Bus about 4 MPix/sec, and PCI
about 12 MPix/sec. The theoretical peak for PCI/33 should be 44 MPix/sec.
This maximum assumes the system handles 24 bit true color intelligently
and that the graphics card and computer are perfect. We haven't found one
yet.
Cascade (also in the phostone.zip
file) pretends to be the very end of Windows Solitaire - if you double
click the obvious king, the cards will "cascade" off the screen.
This test shows the speed of both color and monochrome bitmaps being sent
from the processor to the screen. Hint: notice the speed of the black
non-face cards - they're mono-bitmaps. The remaining cards are
color-bitmaps. Windows uses mono-bitmaps more than you'd think. Cascade
doesn't produce any kind of timing number - it's more of a gee-whiz to
look at.