Bitcoin Forum

Hi guys,

I'm currently trying to build a Bitcoin mining rig and I want to use 4 Radeon 5970's. So far I'm struggling to find any motherboards that have 1 PCI 2.1 port, let alone 4.
Basically, do any of you know how to get these 4 gpu's mining at the same time for the cheapest price? e.g. Not 4 motherboards :P
Any help is appreciated!

-redmist

Not sure about cheap, but this one would work. =)

http://www.amazon.com/LGA1155-Z77-CrossFireX-Motherboard-EXTREME9/dp/B0086T7C62/ref=sr_1_1?ie=UTF8&qid=1362926247&sr=8-1&keywords=asrock+extreme9

you don't need pci 2.1 port...any pcie slot will do, this doesn't affect mining that much, if at all...you can even use pcie x1 slots if you have a pcie x1 extender....

Haha thanks for the help, but a bit too pricey for me  ;)

Oh okay, and I have another question. If i wanted x4 5970's, would they all run at the same speed?

I use Gigabyte B75-D3V, 4 pci slots, bought them for like 55 euro

for mining yes you'll get the same mh/s for all cards unless you sandwich them and you'll be getting high temps...bad for cards, so i suggest pcie extenders

Okay, so using the motherboard that vdragon mentioned: Gigabyte B75-D3V
If it has 4 PCI slots and I get a couple of extenders for it, I should get about 2800 mhash, as one gives about 700?

yep you would only really need 2...one for slot 2,4 to rise them up and let slot 1,3 breathe...but you could also get 4 and just raise them all up and spread them apart...but that's all upto you...i had a 5970 that was on it's way out and it was getting 690mh/s total...have another 5970 in a bamt box and it's getting 728mh/s at 800mhz core clock...

Okay great! Thanks for the info. You seem like you know a fair bit about rigs, so I've got another question of anyone's willing to answer it.

Say I had 6 x 5850's. How would I get them to all mine at once seeing as most motherboards have maybe only 2 or 3 graphics slots?

some mobo's have 5 slots and 1 pcie x1 slot...some have 4 slots n 2 x1 slots...just have to find a mobo that has 6 slots and a psu that can handle that load but with the x1 slot you have to use extenders

Motherboards like MSI BigBang and some Asus Rampage borads have more than 4 slots. Altough (if you have watched my pictures), the max I use on single mobo is 3 cards, and thats recent, was 2 before that. Maybe it will be easier to manage if you dont go for more than 4. Also motherboards like BigBang cost a lot

Well I don't really want to buy a pricey motherboard, especially seeing as this is kind of a budget build. So is there any other way to get all 6 cards mining at once? I mean, there are people out there with 50 cards all mining at once on their super rigs :P
Thanks for all the help guys by the way :)

Okay. So, I've decided finally that I'm gonna go for:
x6 Radeon 5850's
And this motherboard: http://www.gigabyte.com/products/product-page.aspx?pid=3880#ov

Basically, as I'm still really unsure about a lot of this stuff, can any of you guys tell me if I can have 6 Radeon 5850's on this motherboard, and can anyone give me a step by step guide on how to get ALL SIX of them mining at the same time, at their optimum hash rates.
Will give whoever can give me the best help a reward of some sort!!

Really need help on this guys. I want to buy my hardware fairly soon, but I want to be 100% sure that everything will work, as this is a fairly big investment for me  ;D

I would highly suggest against putting 6 5850s on one board. Have you thought about cooling at all? split those 6 into 2 boards, drop that gigabyte board, grab an asrock at 1/2 the price. this one will do x8,x8,x4. http://www.newegg.com/Product/Product.aspx?Item=N82E16813157262 . I have multiple 5830s and 5850s running, again i would not put 6 on a single board. Youre asking for problems, especially as a first timer who doesn't quite seem to understand it all.

Well to be honest it's gonna be in my garage and it's really cold in there haha :) we also have multiple fans :p
So if I had two mobos and 3 cards on each, how do I get them both to mine with the combined hash rate? I want to have the same hash rate as I would if I had 6 cards on one motherboard. :)

That doesnt matter. There is no benefit to loading more cards in one PC, and only drawbacks (power, space, heat). If you're talking about doing a crossfire/sli setup, that actually lowers your output. You wont find a single pro gpu farm miner that has their amd's crossfired.

1. Okay, so I could have two motherboards with 3 cards on each?
2. Would I need 2 separate accounts on a mining pool to do this?
3. How can I have two motherboards on one machine?

Cheers

1. yes
2. no, mining pools operate off of workers. you would simply setup an additional worker (or not, if you dont mind the stats being combined)
3. you cant, you would need two separate cases, mobos, cpus, sticks of ram, psus, and some form of hard drive (whether old ide, newer sata, or a simple usb drive to load up something lightweight on boot like xubuntu or mint).

1.Okay. So it'll be more expensive to build as I would need two machines, but the fact I'm not getting the $200 mobo should balance it out a bit?
2.Right. But if I have 2 workers mining at 1000mhash each, will my profits me the same as if I had one mining at 2000?
3.Okay that's fine :)

1. Correct. Although, if you're concerned with cost - i wonder how you came to choose 5970s - 6 of them will run you around $2k alone on Ebay, used. They're excellent cards, and probably the top hashrate out there, but they use more power, and have an increased base cost. Hope you figured this into your equations.
2. Yes, it doesn't matter. You're not being paid on your mining hash rate, you're being paid on the value of the estimated amount of shares you will get from that hash rate.

1. I originally was going to use 5970's, but I realized they were a bit too pricey and way too hard to get hold of. So I figured I got more hash rate for how much I'm paying for 5850's :)
2. Ok great!!
3. Final thing, if I were to mine litecoin if Bitcoin gets to difficult, would I need to change my rig at all?

3. Litecoin is similar mining wise, only you need more power since it utilises memory of graphics card

No physical change needed, just add in scrypt support to cgminer, or using a diff miner like reaper. all config changes. Honestly, my suggestion would be that you only plan to go with ltc mining. reason being is you obviously havent ordered the parts yet, takes time to ship, assemble, load software, etc. If you purchase today, it will be a min of probably about a week before you're setup (due to company shipping, etc). LTC difficulty will have adjusted 4 times by then. LTC has gone from $0.07 to $0.43 in a week. Get on board now. Also, it's much more profitable to mine ltc and convert to btc than it is to mine btc nowadays. You just cant compete with the big boys.

I would strongly suggest going with LTC from the start.

Great thanks for the advice! I did a few calculations and it seems converting LTC to BTC would be much better.

I've found a good deal where I can get my 6 cards, however there are like 3 different types of 5850. Sapphire, gigabyte and powercooler. I'm gonna go for the powercooler, but do you know if there's any difference between these 3? In terms of hash rate?

Can you tell the exact model of Gigabyte? Gigabyte tend to have best cooling

http://www.newegg.com/Product/Product.aspx?Item=N82E16814125318
Thats the gigabyte version.
Does anyone know if there's a difference in hash rate?

Nah, you should be fine, and end up relatively close. The only issue would be the cooling, like vdragon stated above. Are they all the same 1gb model? I believe some of the later 5850s made by sapphire and gigabyte had 2gb models as well.

Oh okay. Well I wanted to buy 6 of these ones: http://www.ebay.co.uk/itm/PowerColor-Radeon-HD-5850-1GB-DX11-HDMI-DVI-DP-AX5850-1GBD5-PPDH-Graphics-Card-/271161596988?_trksid=p5197.m185&_trkparms=algo%3DSIC.NPJS%26itu%3DI%252BUA%26otn%3D3%26pmod%3D281069556233%26po%3DLVI%26ps%3D63%26clkid%3D6176140186530127789&_qi=RTM1319883

So am I right in thinking that the card I'm thinking of buying^^^^, is still around 400mhash as stated on the Bitcoin Wiki Comparison page? Or is it only the 2GB ones that are that rate? :-\
If that one is 400mhash, I'll go ahead and buy those cards tomorrow!!! :D

you can get 400mhs with a properly tuned setup on a 5850, absolutely. I have my 5830s hitting an average of 330mhs on some pools (and they typically show as max 260 on all info online).

With this cooling on Powercolor, you might aim a little lower. If you can get the gigabyte, go for it.

Really?
Well the rig is going to be in my freezing cold garage. And when it comes to summer, we have a lot of fans that we can just point at it to cool it down.
Thepickingpair, what do you think about that? Powercolor not as powerful??

On the mining comparison I think there was a max of about 450, so if I fiddle around with it, I could definitely get it to 400mhs :D
Just wondering, but what do you think the value of litecoin will be in the Summer?

No one knows, any answer would be speculation. I would say that if you follow the charts from BTC's early days (2011), you would see some strong similarities. There's a possibility it reaches a perfect 25% parity with BTC, and there's the possibility that the previous high of $0.60 was the highest we will see. All speculation.

i think the price will shoot up when BTC diff changes and ASIC goes mainstream. IMO

I absolutely agree. The price will go up on the sheer amount of gpu farms switching over alone.

It has been determined that price drives difficulty, not the other way around.

Obv ASICs will skyrocket the difficulty, but the point stands that a high difficulty will not force a high price.

if that 6 slot board falls though i have a Foxconn Bloodrage X58 i can part with.. its 4x pci 2.0 socket t 1366. Wasnt sure what proc you are running.

http://www.foxconnchannel.com/ProductDetail.aspx?T=motherboard&U=en-us0000430

Thanks for the offer, but I think I'm just gonna go for 2 fairly cheap 3 slot boards. And apart from anything else, my cpu is AMD, so I don't think this would work.
Thanks though  :)

It wouldnt

Definitely not,I definitely have any interest in other alt-coins besides BTC but if what you say was accurate Namecoin should be trading much higher.


I have Radeon 5970's right now and finding it difficult to get both chips hashing away under the new GUI miner scrypt.

Well either way, Litecoins prices are rising rapidly, and I believe they're going to carry on.
Litecoin is supposed to be the silver to Bitcoin's gold, and correct me if I'm wrong, but more people are interested in litecoin than namecoin :p

People are only interested in LTC because they think they can swap all their GPUs over to LTC when BTC ASICs really hit.

Exactly. So having the ASIC's is most probably a good thing for Litecoin. When the ASIC's finally arrive, I reckon loads of people will switch over to Litecoin because it'll be more like Bitcoin was in its earlier days.

Right, now I'm just trying to figure out what motherboard to get. I like the look at the one above, however do you reckon there are any cheaper ones out there that have the same(ish) specs? I'm buying two of these so I want them to be a bit cheaper :)

So I'm a bit confused on what I should do. I can buy these 6 cards later today, however they're the PowerColor ones and I'm not sure if I should get them because of the cooling not being as good.
Thepickingpair, what do you think I should do? Will the cooling make that much of a difference? Or should I just buy an extra fan or something?

 Cooling between 2 cards makes ton of difference. Let me say it like this. When I bought my first 7950s, they were MSI TwinFroz, its a solid card, but that cooling is nothing compared to WF3 on Gigabyte. In a room where I keep the MSIs, I have to start running the air conditioning when room temperature (and outside temperature, since the windows are open) reaches 28C, at that point it becomes hard, because the fans are running at 80%. On Gigabytes, I never ran the air conditioning, They handles 39C outside, and still didnt go up to 100% fan. Simply much better airflow

So it is very important then. Well thats not good as I've got a really good deal with this guy for the 6 cards. So what do you reccomend? Buy 6 gigabyte ones instead?
This is a budget rig, so I don't really want to spend too much money. I'll have a look at the price differences and see what I should do.

Thepickingpair, I've PM'd you by the way. Need some specific help with some stuff if that's okay :)

 How much is that good deal?

It's about £510 I think. So $760.

From my point of view, doesnt sound like it, but I am not sure what rest of the world does. 5850s go for 60-70 euro here

Yeah but on here they've most probably been used to mine 24/7 for a year at least ;)

Wait, I thought I misunderstood? New 5850s in 2013?

Well no, you're obviously going to struggle to find new 5850's now. I mean cards that haven't been used as much as someone using them to mine coins. I'm talking about cards that have been sat in someones PC only being used to play games now and then. Already bought one of that quality a few days ago.