I just bought this video card to get in on some of that VDPAU goodness.
I've got a motherboard (ASUS M2NPV-VM) with a built in GeForce 6150 which I've been using in twinview mode with one monitor connected via VGA and the other via DVI. When the machine boots up both monitors would be clones of the text screen until X-Windows started.
With the new card (Gigabyte GV-NX84S512HP) it seems impossible for both the VGA and DVI monitors to be on at the same time. At boot time only the DVI monitor is on when both are plugged in. If I boot with only the VGA monitor plugged in and then plug in the DVI monitor before X starts then the VGA monitor loses signal and X starts on the DVI monitor.
I'm on an x86_64 system running Gentoo Linux (amd64). Here is the driver and card info from my bug report:
NVRM version: NVIDIA UNIX x86_64 Kernel Module 180.29 Wed Feb 4 23:39:47 PST 2009
GCC version: gcc version 4.1.2 (Gentoo 4.1.2 p1.3)
Model: GeForce 8400 GS
Video BIOS: 62.98.29.00.00
Card Type: PCI-E
DMA Size: 40 bits
DMA Mask: 0xffffffffff
Bus Location: 03.00.0
I've attached the entire bug report. Is it possible that a GeForce 8400 card with VGA and DVI outputs does not support Twinview?