I need advice on a power supply.

[Unforgettable98]

I currently am building a PC. I have an intel i5 4690k and MSI r9 290 4GD5. I bought a 620 watt power supply as I was advised on another thread I posted, but on the the box of the MSI r9 290 4GD5 it says a 750 watt minimum psu. Will 620 watt be fine?

 

[gytisxp]

they take into account you are running the most power consuming components and calculate these power usages that way. It will definetely be enought if the power supply is from a trusted brand ( like 200w headroom even )

 

[YourLocal]

They say 750 Watts but your system might not need 750 watts. The R9 290 does require quite a bit of power undr load but if you bought a quality power supply from a good brand you should be ok.

 

[Math Geek]

exactly what they said above me. what psu did you buy? if it is quality it will be plenty. if it is junk then it won't be enough.

post your model and we can give you an answer easy.

 

[Unforgettable98]

http://pcpartpicker.com/part/seasonic-power-supply-m12ii620bronze

I was advised this psu.

 

[jimthenagual]

That's an excellent psu, great choice.

As for how many watts you actually need, it's best to add up the thermal design power (TDP) of each component, especially the CPU/GPU as they use the most. So something like this:

i5-4690K TDP is 88W
R9 290 TDP is 275 W
rest of system 100W
So at 100% load your system actually only needs about 463W

But it's always a good idea to add overhead of around 150W or so, so your PSU isn't working so hard.
So adding in that 150W of overhead gives you 613W. The PSU you bought is exactly the right amount.