Re: No connected display devices on GeForce 310M with a Sony Vaio
Thanks for the update.
The CustomEDID option is the same workaround that was needed for laptops where we couldn't detect the EDID, which is what was causing this failure. If you're still having this problem in 256.44, then there must be something else that's preventing EDID reads on your system.
Can you attach the output of `acpidump -b -t DSDT -o acpidump.out`?