atcomsystems.ca/forum Forums Computers & Programming Computers, Software, Accessories sound card digital output

I just purchased a diamond 7.1 sound card with a coaxial digtal output(SPDIF) 24bit 96KHz
I have disabled the motherboard sound card
installed it succesfully
as soon as I select SPDIF digital out - it will only allow for PCM 2.0
if I am watching a movie and I select the 5.1 audio instead of stereo the sound is skipping then it shuts the computer down and restarts

Any ideas of what I missed
I have tried 2 different types of sound cards and they both do the same.

Specifically, which Diamond model are we talking about? Are you using PowerDVD 7? Also, Diamond brand cards seem to work with Vista (gasp!) pretty well. Any chance you're using XP?

I've seen this trouble before, and it's usually one of two things. Either your external receiver doesn't truly understand Dolby Digital (AC3), the sound card's driver is busted or the sound card is not actually capable of pre-encoding the audio as AC3 or DTS (causing it to be down-sampled to stereo).

The "Dolby Digital Live" encoding technique handles this perfectly. Some sound cards have this ability--which remains to be seen with yours--and sometime the ability is handled by chips on the PC's motherboard. Which reminds me, you should probably also post such details about your computer.

computer
P4 2.6G running XP Pro
1.5G ram
Intel motherboard D845GERG2
It has 2.2 PCI slots which is what the card requires

I also has windows Vista Ultimate running in the machine with a Dynex 5.1 sound card with the exact same results in Vista and XP
so i thought it was the card so I bought the other one.

Card
Diamond Extreme Sound 7.1
24 bit 96KHz
Amp
Denon 3800CI - definately capable of recieving the signal 24 bit 192Khz

On the denon amp I can see when I am recieving 5.1 or 7.1
It does come up for a second then on/off on/off
then the choppy skipping sound
If I remove the digital SPDIF input from the Denon the same thing happens to the computer
so I am pretty sure it is not the amp

Just a thought, could there be a problem with programs running in the background on the PC? (screen savers etc...?)
I had static/skipping issues when I was converting old audio tapes to wav files, went away afrer I disabled screen savers and Anti-virus programs.

brand new load of windows XP SP2
nothing on it
I just use it for Movies
no firewall,no virus checks,no screen saver
the only programs installed are the Diamond Video card with a DVI to HDMI, and Diamond Sound card with The SPDIF out
all hooked to the Denon amp
It all works flawlessly with PCM/stereo sound
as soon as I try to select the SPDIF for 5.1 or 7.1 all problems occur

Another shot in the dark, Is your PC power supply up to the task? What is the watt ratings?
Maybe trying to push more than 2 speakers is draining the pwr supplly, or do the speakers have thier own power?

Never mind, you're going to an Amp.

550Watt power supply
I had to upgrade it for the Video card