Topic: What I Learned from Building 3x5850 Rigs; May 2011 (Read 8774 times)

Hi fpgaminer. I hope you don't mind me linking my tread to yours. I'm consolidating build discussions

I'm still playing with building myself, but you certainly make a good point about wire shelves. I'm looking at 'tech benches' at the moment, seems a nice compromise between case and no-case (I don't feel entirely comfortable having a board not securely anchored, but I'm kind of a huge wuss).

P.S. I never said thanks for this article, I built most of my stuff before I read this but it was still a good read nonetheless

>I will disclose my adventures and learnings here, for the benefit of fellow Bitcoiners.
thanks,    from your name I had always thought you had a thousand ASICs, but then it's A. only =)

> I will disclose my adventures and learnings here, for the benefit of fellow Bitcoiners.
or... competitors

I could not stand the temptation any longer, too, and built a rig: 4x Sapphire hd5850, among the last to get for a good price. msi 790fx-gd70 - seems fine. AMD 240e. Old hard drive. Cooler Master Silent Pro 1000W (!)

I did not think about four cards not fitting a normal case at all - shock! I was lucky like hell I could squeeze them all in my second old tower  (some drilling is still needed to improve airflow). One of the two cards in the middle runs extremely hot, will have to work something out. still tweaking...

Unfortunately I am not yet fluent in Linux so I went for an old xp license. REMEMBER THE DUMMY PLUGS!

>Ubuntu 11.04 64-bit - Catalyst 11.4, SDK 2.4
why not catalyst 10.12 and sdk 2.1? rumor has it these are better

>Phoenix 1.4 with phatk kernel
gain phatk vs. poclbm?

>Long story short, it worked out just fine and the machines are running fine. But it was nerve-racking worrying about whether the rails >could handle everything. The motherboard was especially worrying, because it supplies up to 75W through the PCI-e ports. 75 * 3 = >225W, or 18.75A. On a 20A rail ...
I really like my cooler master with single rail

>Overclocking: 800/285
>And finally I also experimented with memory underclocking. From stock 1000MHz down to 285MHz.
>Runs stable, and that final tweak seems to be what got me my final numbers. 68C, 66C, and 61C.
what software are you using for tweaking? I have not yet managed to get mine below 600 without crashing... probably I am doing something wrong here

>The on-board GPU worked fine for the first mining rig. [...]
an on-board grafix card is sweet

> ---The first night of running the machines, they were all in my living room with the windows shut. I woke up to an oven, and decided
how could you sleep in there with that three rigs?

>---The last ordeal of my story is something I had completely forgotten to take into account. Circuit breakers. Like most typical homes,
I worry about starting the water cooker or something and the circuit breaker goes off...

feels like it's only worth it if you really like to play and tweak and look after computers. =)

Or if you're very cheap, you can fit 4x dual-slot cards in the Antec 100.

You just need a better case. Look for a PC-K57 or Lanboy. Vendors are slowly coming out with cases with 8 expansion slots in the back and will fit 4 double spaced cards.

The Coolermaster HAF 912 is for me the best mining rig case for a 2 card miner.  You can even properly mount a 2.5" laptop sata drive (my favored drive now) properly without any additional pieces.

I used the ultra-blaster case for other rigs because I got them cheap, but seeing the HAF 912 I just wanna re-case them all now. 

The "mystery case" sounds a lot like my Rosewill CHALLENGER. I find it to be a very nice case, in fact I have two of them. Others recommend cases such as the Antec 100 or one of the CoolerMaster HAF flavors, but for me (I'm only using single cards) the CHALLENGER is a very nice case. I've modded one of mine and mounted two 8w fans to the outside. They won't fit on the inside because they are industrial; they are full metal body and about twice as thick as a normal plastic 120mm fan. I'm not quite sure of the CF/M, but they are loud as hell and keep my card very cool, even when heavily overclocked. This is why I did not go with the cheapest CoolerMaster HAF, because it only have one 120mm side mount.

As far as the Antec 100 recommendation, it was from Diablo-D3, and the more I researched it, the more it makes sense for 3-4 card setups. It can fit two PSUs and has 2 or 3 120mm front intake fans (can't remember off hand.) - It is quite cheap, and I don't just mean in price; the metal looks like an extremely thin gauge and also very sharp. The shipping also kind of kills it, on Newegg it's about $12 to ship it, where-as the CHALLENGER is free and so is the HAF iirc.

Just my two cents; congrats on the builds and I definitely wish you luck in FPGA R&D. I would love to buy an add-in card specifically designed to run Bitcoin that got 30MH/w

Best parts of the post! 

Interesting post, thanks. Do you need to make any specific allowances for CrossFire compatibility to get the best performance out of a build like this, or is it just a matter of throwing the cards in and letting them run independently?

As I've built a 3 card rig, I'll tell you what I did to cool the middle card:

1. I put insulated spaces to separate the cards as much as possible.

2. I drilled 2 sets of holes in the side of the case right next to the 3 video cards and installed 2 fans blowing directly onto the middle card.

3. I set the front and rear fans to both exhaust from the case.

I had all the bits to do this lying about and it resulted in a temperature drop of 25 degrees on the middle card.

Oh man, I forgot about those. Yeah, they're terrible! I took them off (which was easy).

And yes, you're right about the case connectors. Those wouldn't fit a long video card. If you don't have a case, though, you don't need those connectors, so not a huge deal.

But...
Yeah, that's a nice board  . It's a shame the last slot is unusable if you have a case.

But, as I said, I probably wouldn't use a case again. I'd just buy a wire shelf from the hardware store, cardboard, and twisty ties. Heck, you could even use extenders and dangle video cards from an upper shelf with the mobo below it

One thing I will disagree with. That motherboard is stupid. Incredibly stupid. The layout is such that the 3 PCI-E slots are packed together incredibly tightly, with the horrible "push-clip" securing style, and to top it off, the placement of the case connectors and SATA ports are right next to the 2nd and 3rd lanes. This is ok for the sapphire 5850 xtreme, as it is a very small profile card, but a slightly larger, more powerful card will be completely unable to fit due to this stupid placement.

I have some other complaints, but I can't remember them at the moment, as I just threw my hands up in the air after I managed to finagle some things together that wasn't totally awful. So, it can work, but it's really not ideal.

My favorite board thus far is the MSI 890FX-GD70, you can find it a little cheaper than a new assrock if you're lucky and it gives you a whole lot more niceities, even if its a slightly older configuration.

well in a server rack you can stack your stuff as long as you keep expanding to a point. You have more control over airflow too and can probably swoop one up for $400

Server racks (and 4U cases) cost mucho bucks, unless you happen to find the right stuff used.  It'd be nice to have, but from a financial standpoint, it just doesn't make sense when you can make do with having fans by the windows.  In my case, I have A/C, so it's just a bit higher electrical bill than I'd normally see during the summer.

I'm curious if anyone has tried buying a server rack for their rigs and just stack them with a kvm switch and a massive fan / built in fans instead of placing things by the window and or their kitchen (like the one youtube video I saw lol)

youre over hyping single rail design.

it's not that good. multi rail psus are better.

in case of a problem, everything connected to that one rail on the psu would probably go down.

in multi rails- if 1 rail fails, that rail would take what ever is connected to it down with it ( hypothetically ) saving your other parts

How much is this costing you in electricity / home cooling load increase electricity?

Thanks for commenting on my post!

My total hashing power is 3500MH/s right now, but 720MH/s of that is from my original mining rig (cheap 5970 with existing hardware). So I gained an extra 2700MH/s from these new slaves.

$2600 is the total cost after shipping and taxes. The taxes and shipping account for the $300 difference in your estimate

That's about the $1 per MH/s figure I was aiming for, so I'm happy with it.

I'll actually get a little bit of that money back from cashback and bitcoinbonus, rebates, and hopefully selling the free Steam codes that came with the video cards.

Pictures, pictures, we need pictures 

3300MH/s is triple what I currently make (looking at your sig).  I wouldn't be complaining about that!  That's like... $120/day at current rates.  $3600/month... yeah.

Total cost would probably be in the neighborhood of $2300?