which video card is better?

[Jcw188]

I have 2 options:  either I get this video card:  XFX - ATI Radeon HD 6770 1GB DDR5 PCI Express 2.1 Graphics Card and run it on 1 computer.


OR 

I can get 2 of these and run them on 2 computers:  XFX - Radeon HD 6570 1GB DDR3 PCI Express Graphics Card


Which will get me the most Mhash/sec?  Thanks a lot!

[Gator-hex]

Ati 5830 same price more hash.

https://en.bitcoin.it/wiki/Mining_hardware_comparison

[Jcw188]

Thanks for your response but those are my only 2 options. 

Actually, I just saw that the 6770 says it requires a 500W power supply and my comp doesn't have that.  So I guess I have to go with the 6570.  I don't know, I'm trying to figure this out so any help is appreciated.  I have 2 computers, 1 has 300W power supply and other has 350W. Does power supply matter where it says recommended power supply 400W for the 6570?  Thanks

[tysat]

Yes, power supply matters.  Your computer may not be stable if the PSU isn't big enough to handle everything.

[torrentheaven]

For speed comparsion:
https://en.bitcoin.it/wiki/Mining_hardware_comparison

Note if you overclocking GPU to its max it can take like 25% more watts than official max consumption.
Plug no more than 80% of your PSU to it or the life of PSU will be not long.
If you dont have free electricity then you wasting more money than you can mine - or buying coins directly is cheaper.

[Gator-hex]

The PSU guidlines are generally 2x or greater than the actual power draw.

You'll probably draw 200-230 watts.

Worse that happens you break the PSU

If you use PCI-E to molex adapters spread the load out over different power wires.

[Jcw188]

thanks.  from what I've read, I should stick with the 6570 though, as the 6770 needs a lot more power and a separate power connector?  Just seems safer to use 6570 regarding power requirements.

[Fiyasko]

When Adding a GPU to your computer, Its best to NOT HAVE A STOCK POWER SUPPLY OF 250-350Watts!!!
You should have a 400-700watt PSU for crap sakes if your gonna add a 6xxx

[Jcw188]

Ok thanks.  I understand it's best but it's all I have, I'm trying to make do with what I have!  I'm just hoping the 6570's will be functional!