Bitcoin Forum

Why are people choosing the Radeon 5k series over the 6k?  I was going to get 2 6870s with a new intel i7 2600k build for bitcoin mining but I'm wondering if I should choose different dual GPUs.

Getting 2 of these
http://www.newegg.com/Product/Product.aspx?Item=N82E16814150521

Should I get something else?  I'm trying to get at least 2 for under 400$, plus this has free shipping and 2 fans on it :D.


Also, What would be the speed of the Hashes It would be going at?  I looked on the Wiki....it shows around 270-320Mhash/s each card depending on clock.

The 58xx series cards have a lot more stream processors than the 68xx series, so they produce higher MH/s rates. I have been testing a 5850 and at 850MHz on core i get 330MH/s. I have just brought a 6870 which i will be testing tomorrow, i can report back tomorrow at to the difference.

5850 = 1440 stream processors
6850 = 960      "              "
6870 = 1120     "             "

That and it's cheaper.

So, what's a dual 5k series GPU I Can get for under 400$ that would be faster than dual 6870s  ;D

Guessing 2 of these?
http://www.newegg.com/Product/Product.aspx?Item=N82E16814125318

I'm looking at the GPU mining comparison charts and it seems like those 2 cards aren't far off from each other.
https://en.bitcoin.it/wiki/Mining_hardware_comparison
Also, I would have to overclock the 5850 up to maybe 900MHZ before hitting 300Mhash/s.....hmm
So....5850 or 6870?

Like i previously said, my 5850 at only 850MHz gets 330MH/s. I'm going to be testing 6870 today to see how much OC is required to reach the 300MH/s mark.

Good luck getting some.

That's what I'm worried about :(, when do they restock?   :(

Report back on that to me please, that would be great :D.

Well if I had to choose between a 5870 and a 6950, I would go with the 6950. It is the same price, and IF bitcoin ever fails, you can just resell the parts for a minimal loss. Also, in regular computing (F@H/gaming) the 6950 is about 35% faster than a 6950.

You should fix this so I understand you.

Ok so far, at an OC of 1000MHz on the core of the 6870, im only hitting 290MH/s. At stock speeds it only gets 260MH/s. 5850 is a much better choice, of a 5870 if you can afford one.

Problem is finding a 5850 or 5870. The 6870 is basically equal to the 5830 for btc mining. Same number of shaders. Running a 6870 at the same 975mhz core clock and 300mhz memory clock as my 5830's gives me ~296 mh/s on the 6870 while I get ~301 mh/s on the 5830's. So basically a wash, hashing wise. Of course the 6870 is around $50 more than those Sapphire 5830's that Newegg had.

Can't find dual 5850s anywhere for under 400$  :(.
Maybe I'll just get what I was gonna get and mine at around 550-600 Mhash/s instead of 600+

69x0 uses more [bit slower]VLIW4 shaders instead of VLIW5 shaders in 58x0, performing comparable.
but 68x0 consume notable less power per.

n/a