I have system with a DP35DP with the latest bios 0572 and 2GB of ram. It has three displays working fine. The displays are driven by an PCI-e 9600GT Nvidia (2 monitors) on PCI1:0:0 and a PCI 8400gs Nvidia running the third display on PCI 8:0:0
I rencently upgraded to 8GB of ram and the displays stoped working. I know the RAM is and the video cards are OK because:
1) 2GB + 8400GS = Works
2) 2GB + 9600GT = Works
3) 2GB + 8400GS + 9600GT = WORKS
4) 8GB + 8400GS = Works
5) 8GB + 9600GS = Works
6) 4GB + 8400GS + 9600GT = DOES NOT WORK
7) 8GB + 8400GS + 9600GT = DOES NOT WORK
So basically all combinations work execpt 6 and 7. Some how with 4GB or more none of the video cards gets initialized on the PCI bus.
After I put the 8GB the syslog started showing these
pci 0000:01:00.0: BAR 6: can't allocate mem resource [0xe0000000-0xdfffffff]
pci 0000:08:00.0: BAR 6: can't allocate mem resource [0xf0000000-0xefffffff]
nvidia: probe of 0000:01:00.0 failed with error -1
nvidia: probe of 0000:08:00.0 failed with error -1
heci: Failed to get pci regions
NVRM: The NVIDIA probe routine failed for 2 device(s).
NVRM: None of the NVIDIA graphics adapters were initialized!
EDIT: Could all this be related to http://tjworld.net/wiki/Linux/Bug/PciAllocationAlgorithm
Message was edited by: alexcuervo
I'm just presenting a wild guess now, but could it be that the PSU don't have enough power to run all the stuff that you put into the computer? That could explain why it's not working when you put in both of the graphics cards at the same time as all the memory.
I believe that the memory doesn't take too much power but it might be that you are at the edge already and this little extra power consumption makes the computer not to start.
As I said, it's just a wild guess but it is worth checking if you don't have a more powerful PSU.
A quick update.
I was NEVER able to resolve this issue.
I needed the 8GB of ram and also the three displays. So the only thing I could do was to replace the two existing video cards for one video card able to drive three displays.
I replaced the 8400GS and 9600GT cards for ans NVIDIA NVS 450.