Question Nvidia NVS 300

A little bit probably, depends on the cooling and power budget available. But that is a quite old GPU. 2009 or so, with its inclusion to the NVS 300 in 2011, so they built it using a two year old GPU, and was low end even when it was new.
 
That appears to be a very open ended question in Linux. Many recommend using the command line, but there are also also many GUI options.

LACT came up in my searches. (Nor do I know if such an old GPU would be supported, it may rely on more contemporary means to manipulate GPUs)

My current Linux system has Intel Arc in it, so I have no direct experience overclocking Nvidia.
 
That appears to be a very open ended question in Linux. Many recommend using the command line, but there are also also many GUI options.

LACT came up in my searches. (Nor do I know if such an old GPU would be supported, it may rely on more contemporary means to manipulate GPUs)

My current Linux system has Intel Arc in it, so I have no direct experience overclocking Nvidia.
Ah, okay, I'll have to see if it works.