A Dell Latitude E6430 had Windows 7 reinstalled this August, and the firmware was upgraded along to revision A15. Somehow the firmware setting for Optimus video got disabled and I regrettably missed the change.
Today, while upgrading the firmware to revision A16, I spotted the disabled Optimus video setting. Thus, I enabled the setting, and now both the Intel HD Graphics 4000 and the nVidia NVS 5300M graphics cards show up in Computer Management. Just remember to install the Intel HD Graphics 4000 driver prior to installing the nVidia NVS 5300M driver.
Hopefully, all stability issues we’ve seen lately should now be resolved.
I began to question if the firmware update process is always able to restore every setting. The moral of this story is to verify the firmware settings after each upgrade.