MS 400W PSU or 550W good? GTX 1050

kefi.nana

Prominent
Oct 28, 2017
21
0
510
I have a prebuilt OptiPlex 980 MT with a
I5 750 2.66GHZ (turbo 2 cores on 3.3GHZ)
AMD R7 240 2GB
8GB DDR3 RAM
250GB HDD
255W Dell PSU

and i want to upgrade to an GTX 1050 or GTX 750 TI i would want a 1050. I found these three PSU's for pretty cheap.
PSU MQ MISSION Q 400W - 18$
PSU MQ MISSION Q 550W - 23$
PSU MSI 550 440W - 23$
And its gonna stay a long time in my pc because im not gonna upgrade it for a while. Thanks in advance :)