2 x R9 270 + 2 x 7870 PSU?

[elpibemaxi]

Hey guys what size PSU would I need for 2 x 270s and 2 x 7870s? (total 4 gpus)
Rest of the rig is:

Athlon II X2 240
Asus M5a97 Le R2.0
4gb DDR3
1 7200rpm HDD

I tried with a few calculators online but they're throwing something like 650W which I think it's too low, isn't it?
Do you think a 850W psu will do?

Appreciate your help guys, cheers

[Undefeatable]

Hey guys what size PSU would I need for 2 x 270s and 2 x 7870s? (total 4 gpus)
Rest of the rig is:

Athlon II X2 240
Asus M5a97 Le R2.0
4gb DDR3
1 7200rpm HDD

I tried with a few calculators online but they're throwing something like 650W which I think it's too low, isn't it?
Do you think a 850W psu will do?

Appreciate your help guys, cheers

850W should be enough but I would go with 1000W cause I don't want PSU to run hot!!

[elpibemaxi]

ok thanks for the tip bro. I also have another doubt, I don't know if I should get:

1) 2 x R9 270 + 1 x sapphire R9 290
or
2) 2 x R9 270 + 2 x 7870 sapphire ghz edition

What do you think? I thought of the 2 x 7870s because I live in a very hot area, and from what I've read the reference 290 cooling is not that great. Also I can get them slightly cheaper than the price of 1 R9 290.
The kh/s should be similar at around 800-850 right?

[Gator-hex]

R9 270 = 1x 6-Pin = 75W + 75W from the motherboard = 150W max.

HD 7870 =  2x 6-Pin = 150W + 75W from the motherboard = 225W max.

add 100W for your CPU/Motherboard/Memory/HDD

150+150+225+225+100 = 850W

This doesn't mean a 850W PSU though, it means 850W +12v Rail.
A power supply can call itself 850W but may only have a 750W on the +12v rail so watch out for that.

R9 290 = 1x 6-pin = 75W + 1x 8-pin = 150W + 75W from the motherboard = 300W max.

150+150+300+100 = 700W