I have the following system config:
nforce 780i SLI Motherboard
PVR-250 card
Fedora 8 with all  updates.

I had a real struggle getting this card to work in a stable way. I was wanting 
to get some other peoples thoughts on this.  I have had this card for a long 
time, just so you know.

First I started out with Fedora 7 all updates applied.  The card gave me 
multiple errors including the dread DMA timeouts. The others were when 
watching TV on it, I would get the buffer's full errors, and application not 
reading fast enough, blah, blah, blah. Video play back quality was not very 
good to say the least.

Finally, upgrade to Fedora 8 which yum updates install kernel version 
2.6.24.4-64.fc8.  One set of problems went away. The video play back looked 
great no longer getting the buffer full errors. However, the DMA timeouts 
remained, usually occurring fairly quickly within around 10 mins or so.

Went through all the how to's and troubleshooting, and finally started playing 
with the pci latency settings.  Through MUCH trail and error I finally am 
using the following settings:

In the bios I have the default set to 176 for the pci latency.
In my rc.local startup I am using the following setting:
/sbin/setpci -v -s 05:09.0 latency_timer=80

Obviously the default of 64 never worked here. And the bios default was the 
standard 32.

The only PCI card in the system is the PVR-250. And according to the lspci 
output the only pci device listed with the latency of 176 is the intergrated 
firewire adapter. All other intergrated devices I am fairly certain are 
PCI-Express. 

So the question is why did I even have this problem?

Also is there not a better way to troubleshoot pci-latency other than by trail 
and error?

Is it possible that the default of 64 is still a little low?

I am tempted to try a setting of latency_timer=60 just to test it. But I am 
kinda tired of messing with it for now. I spent almost two days on this.

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