Can a psu bottleneck CPU/GPU performance

[gogi]

I know this has been asked a lot of times.
But im having problems with my GPU usage
examples:
http://i.imgur.com/xinv1Ej.png
http://i.imgur.com/UzAuzjb.png
http://img19.imageshack.us/img19/5938/7a09872242a041738f7a764.png

could this behavior be due to my PSU (a crappy LC Power PSU ''600W'')

system specs:
AMD FX 8120
gigabyte 6870 HD
8GB ram

 

[Ubrales]

If the PSU cannot supply the peak and the constant power required, then it will shut off the PC. Or rather, the PC will shut itself off.

 

[kitsunestarwind]

PSU cannot reduce the performance of a PC, if it cannot supply the required voltage/current the PSU will shut down due to UVP (under voltage protection) your parts will not clock down due to low voltage (no matter what anyone says)

If your PSU does not have UVP and the voltage continues to drop this will lead to stress on the voltage regulators, resulting in either a Burnt out PSU / Motherboard or GPU