In a lot of distros, vdpau which accelerates video through the GPUis often not installed even in recent distros. This will result in Firefox with Youtube dropping frames when you check the "Stats for Nerds" and to the eye as jerky or slower video playback due to the dropped frames.
Some sites will say that because you are watching VP09 that there is no GPU support, but with vdpau installed and enabled, many GPUs will still be able to use hardware decoding for 4K........
Iused the slightly older "304.117" version and it worked.
With the newest version Icouldn't get X to start and kept getting these errors in messages/dmesg.
[ 2346.083660] nvidia 0000:01:00.0: irq 44 for MSI/MSI-X
[ 2350.608342] NVRM: RmInitAdapter failed! (0x12:0x2b:1831)
[ 2350.608354] NVRM: rm_init_adapter failed for device bearing minor number 0
[ 2350.608369] NVRM: nvidia_frontend_open: minor 0, module->open() failed, err........
One thing to remember is that you need MegaCli to do the flashing.
You also need the correct file,I tried at least 2 different Perc 6 firmwares from Dell that kept getting rejected as corrupt by MegaCli(they were really the wrong version). I have an external PCI-E Dell 6 Perc/I butI chose images from the 'Integrated" on motherboard version as it was allI could find. They are different, and below is my first time finding success.........