Which psu for 7850?

[asdjei]

hello everyone,
I'm planning to buy a gfx card to go with my new system. my system config is

core i5 3470
4GBx2 DDR3 RAM
Intel B75 mobo
Samsung DVD writer( don't know the model, bought it back in 2010)
1TB HDD
Samsung 21.5" 1080p

I'm looking at three cards, the Radeon 7770, the Geforce 650 Ti and the Radeon 7850..however, my PSU is only a 400W one by Cooler Master, and I think it might prove to be a bottleneck..between the three, which is the best card that will go with my system? Also, the 7850 is at the edge of my budget, I probably won't have any money left for a new psu(if needed)

And i will not be doing any sort of overclocking whatsoever. thanks!

 

[Norlag]

The 7770 and the 650 ti can run on 400 watts, but the 7850 requires at least 500 watts. The 650 ti performs better than the 7770, and the 7850 performs best of all of them. So unless you plan on upgrading the psu, get the 650 ti.

If you do get a new psu, get one that is 80+ certified. Your power bills will thank you.

 

[asdjei]

The 7770 and the 650 ti can run on 400 watts, but the 7850 requires at least 500 watts. The 650 ti performs better than the 7770, and the 7850 performs best of all of them. So unless you plan on upgrading the psu, get the 650 ti.

If you do get a new psu, get one that is 80+ certified. Your power bills will thank you.

thanks. BTW about my psu, I looked at it, said on the PSU that it had two 12V rails(+12 and -12) having 16 amps each..it also said that there was a 5V and a 3V rails(not sure about the amperage of those)..also said that the max power output was approx 327W..does that make it an 80+ PSU? it says RS 400 PSAR 13 on the psu.

sorry if I seem like a noob, I just thought that 80+ certification you mentioned was about the effective wattage of the psu..or rather the percentage of wattage delivered..

 

[slomo4sho]

The PSU should indicate its performance level on the box.

Also, I have a similar setup as yours for my HTPC but am running a 1gb 7850 with a i7 3770K (don't ask) on a 400W PSU. The card is only rated at 125W so your total system load shouldn't exceed 275W.

If you have a generic PSU that is not 80+ certified than you may run into issues with your setup. Otherwise there should be no issues.

For reference, my system has a PC Power and Cooling Silencer Mk III Series 400W PSU
http://www.newegg.com/Product/Product.aspx?Item=N82E16817703034

Lastly, some 2gb versions of the 7850 require two 6 pin connectors which most 400W PSUs wouldn't accommodate. Be sure to check the power connectors when purchasing your card.