Should/Can the Power Supply Move?

[aQuestionMark]

I am building a PC for the first time. I am using an EVGA SUPERNOVA Power Supply and a NZXT Noctis 450 case. I have quickly and easily put the power supply into the case, but there are some places in the power supply for screws to screw in the power supply to the case. Is it necessary to screw in the PSU? Is it okay if it moves a bit? Where do I get the screws to screw it in if necessary (Are they packaged with the case/PSU?)? Please help!
Thanks,
Question

 

[aQuestionMark]

Note: I looked through my case box and there are NO EXTRA SCREWS.

 

[bigpinkdragon286]

https://www.amazon.com/Maxmoral-100pcs-Toothed-Hex-SCREW/dp/B0186SF00C/ref=sr_1_cc_1?s=aps&ie=UTF8&qid=1495847205&sr=1-1-catcorr&keywords=6%2F32+pc+screws

Most cases come with extra screws which can be used to mount the PSU.

Power supply should be firmly attached. Theoretically, it will help with grounding. Also, it could damage a PCB either physically or electrically if it ran into it just right.

Provided the PSU isn't bouncing around during use or resting on parts it isn't supposed to, I doubt you'll actually experience any major malfunctions if it isn't screwed in.