Should I perform scaling on display or GPU?

[Lezukion]

I'm using a 32 inches 1080p Full HD Vizio TV with a HDMI cable for my PC. In Nvidia control panel, should I set perform scaling on display or GPU? What is good and what is bad for each one? Also, if I set perform scaling on GPU, will it take some load on my card? Thank you

Edited: Lastly, should I check the box "Override scaling mode set by games and programs"?

[chiefputsilao✖️ping]

idk which is better but when i set scaling on gpu, i can play starcraft: broodwar on its native (?) 4:3 scale on my 20" led monitor, 1600x900 resolution.
the game is on the center of the monitor screen and is bordered by 'black'.