With the Nvidia official drivers you are able to throttle the performance of the nvidia graphic cards (gpu) to the maximum. However there are small glitches that need to manually fixed.
After installing and enabling the nvidia proprietory drivers you would notice that the grub screen and the Ubuntu splash screen (called Plymouth at startup and shutdown are displaying in a low resolution graphics mode. It is generally as low as 640x480 px.
The low resolution is caused because the Nvidia graphics drivers are not yet loaded at the point of grub screen and splash screen. At that point the system can display whatever resolution the graphics card supports via the VESA BIOS extensions. 640x480 being the most viable resolution, is used hence.
The splash screen being in low resolution is not likely to cause any problems, but the grub screen should have a better resolution when you need to work at the grub console for example.
So this quick tutorial shows you how to fix the resolution at these screens. Note that this has only been tested on Ubuntu 14.04 and many other users have reported issues with this method either not working or causing a blank screens at different places.
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Fix low resolution grub and splash screen with Nvidia drivers on Ubuntu 14.04