Larry:
As I said, DirectX implementations depending heavily on the hardware
and the drivers. When I engage directx with my ATI Radeon 9800, I get
an immediate factor over 2 drop in CPU ticks! When I use it on my
Nvidia card at work, I get a larger drop. When I use it with the ATI
Radeon Mobo card on my laptop, the CPU drops on average by a factor of
two. Coupled with the use of SSE2 in the FFTW arithmetic, this winds
up being a factor of FOUR on my laptop. This is due to faster graphics
plus fast computation of the filters.
These numbers are huge as you can imagine. The graphics systems was
clearly a severe limiting factor in the performance of the code system.
There was really no way for us to know what we would find at the end of
the day due to the large variance in cards and drivers. For the time
being, the implications are clear: Use the graphics system that gives
you the best overall performance. The DirectX (really managed DirectX)
is new to us all and will take time to work out in detail (hopefully not
as long as the sound card issues took for us to completely understand).
Bob
Larry W8ER wrote:
Bob,
Maybe I don't understand your POS statement exactly. I am seeing what
everyone else is seeing with respect to DirectX and I am sure that
Eric is busting his chops on this. Eric always does! By activating
DirectX on my system, I see the CPU utilization rise from 3% or 4% to
anywhere between 40% and 50% with the panadapter display. I have never
thought of my 2.8 gig Pentium 4 and Intel 865 mobo (including onboard
Intel video) as a POS. Does your post mean that I could get better
performance from some other add in video card and if so, what would
your recommendation be?
BTW Preview 8 is a darn nice Christmas present. Thanks Eric!
--Larry W8ER
--
Laziness is the number one inspiration for ingenuity. Guilty as charged!
