How big of a PSU Should i Buy?

[Matt_matrix]

preforming a system upgrade soon; cant figure out how much PSU Wattage headroom i need, as calculators seem to give me a strange plethora of various requirements for the specific hardware im going to get... so heres a run down of what i will have; hopefully someone can tell me how much i need?

CPU: FX-8320 @ 4.5Ghz
Cooler: H80i
Fans: 2x 120m, 10x 140mm
Drives: 3x 1TB WD Black, 1x 2TB Hitachi HDD, 1x SSD
GPU: GIGABYTE R9 390
Disk drive/ burner

Figured i needed at least 750 Watts for all this; but now im starting to think ill need 850 to ensure my Systems psu isn't strained; or under constant near full load...
I Did some Looking and found this PSU From EVGA... Will it be enough?
http://www.amazon.com/dp/B00K85X23O/ref=wl_it_dp_o_pC_nS_ttl?_encoding=UTF8&colid=1272QA079IRNZ&coliid=I2GAQTTGVP83FL&psc=1

 

[bignastyid]

A good 650w PSU would be fine. 750w will provide ample headroom. Don't get the B1 version get the B2, G2, GS, GQ or P series if you want EVGA.

 

[Matt_matrix]

A good 650w PSU would be fine. 750w will provide ample headroom. Don't get the B1 version get the B2, G2, GS, GQ or P series if you want EVGA.

your obviously more competent when it comes to PSU's; but out of curiosity whats wrong with The B1?

 

[geofelt]

Calculators are deadly accurate if... you can know what to enter.
Capacitor ageing, future upgrades, oc% for example.
We just can't know those answers.
Here is a handy chart.
Your R9-390 will want about a 650w psu.
http://www.realhardtechx.com/index_archivos/Page362.htm

If you are planning on crossfire(which I do not recommend) then you are looking at 1000w.
More likely, the next gen cards from amd or nvidia will be much less power hungry and will still run on 650w.
You will avoid multi gpu issues with a single strong card.

I have no problem overprovisioning a PSU a bit. Say 20%.
It will run cooler, quieter, and more efficiently in the middle third of it's range.
A PSU will only use the wattage demanded of it, regardless of it's max capability.

Try to buy a tier 1 or 2 unit from a quality list such as this:
https://community.newegg.com/eggxpert/computer_hardware/f/135081/t/45344.aspx?Redirected=true

The evga is OK, but you can do better.
Look for Seasonic or XFX which is make by Seasonic.

 

[bignastyid]

The B1(made by FSP) is lower build quality. The b2 version(made by SuperFlower) is much better.

 

[Matt_matrix]

Calculators are deadly accurate if... you can know what to enter.
Capacitor ageing, future upgrades, oc% for example.
We just can't know those answers.
Here is a handy chart.
Your R9-390 will want about a 650w psu.
http://www.realhardtechx.com/index_archivos/Page362.htm

If you are planning on crossfire(which I do not recommend) then you are looking at 1000w.
More likely, the next gen cards from amd or nvidia will be much less power hungry and will still run on 650w.
You will avoid multi gpu issues with a single strong card.

I have no problem overprovisioning a PSU a bit. Say 20%.
It will run cooler, quieter, and more efficiently in the middle third of it's range.
A PSU will only use the wattage demanded of it, regardless of it's max capability.

Try to buy a tier 1 or 2 unit from a quality list such as this:
https://community.newegg.com/eggxpert/computer_hardware/f/135081/t/45344.aspx?Redirected=true

The evga is OK, but you can do better.
Look for Seasonic or XFX which is make by Seasonic.

i contemplated crossfire; Heat would be the main issue of course, as these particular R9 390s are terrible for that; all that horse power would be nice; but it would be to much of a hassle getting everything set up the way i would want it; i would HAVE to have all Noctua or equivalent fans, and all that to move the air; id probably need a good AC unit too for the room to even be habitable...

 

[Dark Lord of Tech]

PCPartPicker part list / Price breakdown by merchant

Power Supply: EVGA SuperNOVA GS 650W 80+ Gold Certified Fully-Modular ATX Power Supply ($79.99 @ Amazon)
Total: $79.99
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2016-03-23 13:35 EDT-0400