Getting ahead of arriving miner parts... (with 25LTC bounty)

[cptmooseinc]

Okay, so I've done quite a bit of research and finally ordered my rig parts. I've built plenty of computers before, but haven't ever messed with trying to cram 6 GPUs on to a single board. I have 5 16x risers and 1 1x->16x riser on the way for each board (I'm building two identical rigs). I have everything to build the systems arriving on Thursday for assembly on Saturday/Sunday. I will be buying a steel rack from either Wal-mart or Sam's on Saturday to put the first two rigs on.

Here's my parts list:

2 - Gigabyte GA-990FXA-UD5 Motherboards
2 - AMD Sempron 145 CPUs
2 - LEPA G1600W PSUs
12 - POWERCOLOR AX7950 GPUs
4 - 8GB Mushkin DDR3 RAM
2 - 250GB Seagate HDDs
1 - 30g tube of Artic Cooling MX-2 (got a lot to have extra for additional rigs down the road).

I don't have any spare Windows XP CD keys/install discs anymore, so I guess I'm going with Linux. I've had some limited exposure to Linux before, but not much.

My question is, what flavor a Linux would be best to install on these hard drives to make setting up the mining programs the easiest? Also, which mining program (Reaper, CGMiner, etc) would be best for these cards? I'm going to be attempting to tweak the settings on these cards if they are unlocked (hoping they are). If they are unlocked, the person who helps me get the maximum -STABLE- kH/s out of the card will get a 25LTC bounty paid to whatever tip jar you tell me to send it to. It shouldn't take 12 GPUs too long to produce 25LTC. (:

Also, for that Gigabyte UD-5 motherboard, does anything special need to be done (shorting pins, etc) to get all 6 cards working on the board properly?

Any help will be much appreciated. I have lots of links to various guides and settings tweaks already, but am always looking for a little extra edge/tips and tricks if they are to be had. Again, I won't be ready to build until Saturday morning, but after that.

[1714062156]

1714062156

[cryptodrifter]

Please note. From info/reviews i've heard, Powercooler cards are not good for mining. I wish i could elaborate more though.

But from what I've seen/researched, powercooler = not friendly to miners.

[cptmooseinc]

I've heard that the ones I got (AX7950) were. Can anyone confirm or deny this?

[cptmooseinc]

Just an update...

I have ~$10k about to be on loan from a family member for two years to do what I want with. They know I intend to build 4 more miners with it. I will probably keep building clones of the setup I quoted, but does anyone have an unlocked 7950 GPU that has been tried and true to them under the constant load of mining? If these Powercolor AX7950 GPUs end up not standing up to the test, I'm going to need something to replace them with and buy in the future.

Also, what exactly is best to stand these GPUs up on (on their side of course) when putting them on a steel rack like I've seen so many others do. I figure I could put about 2 miners per shelf and have 4 shelves, so that'd be alright. I saw someone who used what looked like cooling racks for a serving dish and that's what I'm presently planning on buying at the store this weekend. Do you guys usually screw the mobos into the wood shelving or just let them sit?

[zif33rs]

havent done litecoin mining but I do have a powercolor 7950 that I have been using to mine bitcoin for the last month. So far it has been rock solid. The only problem I have with it is the reference cooler. The single 92mm fan is just not enough. Also the way the heatsink is set up dosent have direct contact with the memory chips. All in all not a great thermal solution. That being said I use cgminer and get 620 mh/s. I just bought a 2nd sapphire 7950 that performs just as well and has a better 2 fan/hs combo and was 30 bucks cheaper. 2 at 620 mh/s is better than 1.       12 would be awesome. Be prepared for the heat.

[cptmooseinc]

Care to share you settings for that Powercolor 7950? (: I'm going to need them! Hahaha. What'd you do to overcome the reference cooler problem? Can I just put a desk fan blowing across them like I intended to and that will resolve the problem or must I modify them in some way to not overheat them?

Also, the Sapphire 7950 you speak of, it wouldn't happen this one would it?: http://www.newegg.com/Product/Product.aspx?Item=N82E16814202006

If so, is it unlocked? I'd gladly buy these next time. I just heard that reference cooler GPUs were your most likely candidates to be unlocked. Those Sapphires look so NICE!

Thanks man,
-Moose

P.S. I noticed the Gigabyte UD5 mobo has no onboard video. So I will have to use one of the GPUs to install everything and get it working. How exactly do I get that GPU to mine if I'm using it for the display? Or can I turn the miner on for it and then disconnect the display and let it run as such? I plan on just grabbing a keyboard, mouse, and cheap monitor to use to set up all these various builds.

[zif33rs]

My card will run 1225mhz at 1.300v but the sweet spot for me is 1175mhz gpu core @ 1.250v  1000mhz memory  -I 9  fans@75% powertune +10%

I did remove the heatsink fan combo from the powercolor unit and redid the TIM using Noctua N-1. I also removed the plastic "shroud" and just left the aluminum hs/fan exposed. I saw about a 5c drop in temp doing this.

The sapphire I just got appears to be unlocked as far as I can tell..havent needed to set voltage above 1.250v for my 1175mhz oc so...all is well with it and that outstanding price.

I was using a regualr desk fan with one card and it was ok..room was starting to heat up tho with the door closed. I now have the unit next to the window ac unit with both card running full bore. Ready for summer. 

Check some of the threads here for milkcrate setups. Been thinking about moving to something like that. For multi rig set ups like your planning I would go that way for sure.

And yea..I am a Egghead. Got both of em thru there. Hard to beat the prices and ffs..they deliver to your door.


I have the A10-5800k apu with a biostar a85w motherboard. It lets me net another 150mh/s thru the onboard gpu. 

Pretty sure once you have everything up and running you can disconnect things. Maybe a KVM switch or something?

[cptmooseinc]

Never heard of Noctua-1 before. Can I just use the Arctic Cooling MX-2 instead?

Also, I've seen the milk crate setups and think they're neat, but I'm not exactly sure how I'd get my hands on some milk crates. :p

[zif33rs]

Should be fine with MX-2. I think it has to be non-conductive is all. That N-1 is the shit tho..get some if you can. Notable difference.

Try looking for a local dairy.

[LivesUnderTheBridge]

I can tell you what not to do.

Don't use cgminer w/ Ubuntu 12.04.

In short, AMD Catalyst 13.1 is what is easy to get on, although the developer doesn't suggest using newer versions. From what I gather, 12.8 seems to be one of the best (possibly 12.10). Both of these versions won't install on anything higer than XOrg 6.9 (if I remember correctly) and it's no easy task to downgrade X.

Right now I'm trying out Xubuntu 12.04 and hopefully it won't have the video driver problems that Ubuntu 12.04 has, if not I'll have to go to natty narwhal (Ubuntu 11.04) so I can run the old drivers. See below for a list of the most helpful guides I've found.

cgminer w/ Xubuntu 12.04 https://docs.google.com/document/d/1Gw7YPYgMgNNU42skibULbJJUx_suP_CpjSEdSi8_z9U/preview?sle=true
cgminer w/ Ubuntu 12.04 http://rdmsnippets.com/2013/03/20/bitcoin-mining-with-ubuntu-12-04-tls-and-cgminer/ (Great guide! doesn't work on my 4 card rig unfortunatly, maybe)
BFGminer w/ Ubuntu 12.04 https://deekayen.net/xubuntu-precise-bitcoin-mining (not terribly helpful, but good for testing)

[cptmooseinc]

Thanks! Keep it coming guys! (:

[cptmooseinc]

Crap...somehow I underestimated how many amps these rigs would be producing. It seems that my 1600W PSU would draw about 13.3A. The breaker I planned on running two rigs on is only a 20A breaker. I'm gonna stop at Home Depot and get a Kill-A-Watt reader to see exactly what this thing draws to hopefully squeeze two rigs on to it. Now I might have to put my other 4 rigs on hold until I find a solution for the power needs per rig. :-/

Am I doing the math right to calculate amps??? I know the rig won't use the full 1600W, but I just wanted to know the -max- such a setup could use per rig.

-Moose

[LivesUnderTheBridge]

Crap...somehow I underestimated how many amps these rigs would be producing. It seems that my 1600W PSU would draw about 13.3A. The breaker I planned on running two rigs on is only a 20A breaker. I'm gonna stop at Home Depot and get a Kill-A-Watt reader to see exactly what this thing draws to hopefully squeeze two rigs on to it. Now I might have to put my other 4 rigs on hold until I find a solution for the power needs per rig. :-/

Am I doing the math right to calculate amps??? I know the rig won't use the full 1600W, but I just wanted to know the -max- such a setup could use per rig.

-Moose

Yeah, they'll be every bit of 14.5 amps at full bore. If you get a brown out, it'll trip a 15A breaker.

Divide Watts by volts to get amps. If your voltage drops to 90, your draw will jump to 17+A. I suggest putting a UPS in if you have less than stellar power.

If you want to check your draw, I suggest you get something like this. You'll thank me later. http://www.harborfreight.com/digital-clamp-on-multimeter-95652.html

http://www.harborfreight.com/media/catalog/product/cache/1/image/9df78eab33525d08d6e5fb8d27136e95/i/m/image_22081.jpg

Don't forget to pick up a few extra breakers while you're there.

[cptmooseinc]

The place I live is brand new (opened in Oct 2012) with great wiring. Just not a lot of amps to draw on. I can get 2 rigs, maybe 3 in this apartment maximum. I guess I'm going to look for a place to rent out that has more 240V connections that I can get 40A breakers on. Then each rig should only pull 6.5A and I can could get about 6 rigs per 40A 240V breaker. (:

[mco65]

If its a brand new place, you don't reckon they used 10 gauge wire on those 20amp ckts?  If so, you can probably just swap out the 20amp breaker for a 30amp breaker.. just make double damn sure you have 10 gauge wires vs 12 or 14.. 

[cptmooseinc]

I think this is just a sub-breaker box. I wouldn't know how to kill the power coming it to it to make the swap. I have a coworker that was an electrician for years. I may have him come look at it.

I just called a couple of places (one is a 45 second walk from my apartment) that would rent me an office for $900/mo. One has utilities included, but I made sure to mention how much electricity I'd use. He'd be willing to drop off the average tenant usage from the rent and just let me pay the electric bill. It would be a pretty sweet deal for 6 miners to start and an even better deal when I get all 20 miners in there. Going after this next week (I have training and will be out of town) to check them both out. One of the buildings for sure has some 240V lines in them with big nasty breakers so I could put a -LOT- more rigs in there. We'll see who ends up winning.

I've put a list together of supplies I need to go and buy this evening. Then I think I'm going to work on assembling the rack or whatever I decide to buy and start taking off the plastic covers from the GPUs and redoing the thermal paste on the heat-sinks.

[cptmooseinc]

Got one system put together barebones with 1 card just to get Ubuntu installed and have it setup before dumping 5 more cards on to it.

I'm running into a problem with my GA-990FXA-UD5 motherboard. I know the Sempron 145 CPUs are supposed to have a locked second core which is easily enabled by swapping out a setting in the BIOS to check for hidden locked cores on the chips. I enabled the setting and rebooted and after that the system just goes through endless reboots after always trying to get back into the BIOS settings on its own. It takes clearing the CMOS to get it to stop doing it.

I don't necessarily -NEED- the second core, but I would like to unlock it and have the system work if at all possible. I'm using the latest version of the BIOS already. Any tips or other settings I need to change? The manual doesn't show needing to do anything else. If I can't figure it out tomorrow, then I'm just going to leave it as is. I just like the idea of a free 2nd core. (:

-Moose

[MaGNeT]

Got one system put together barebones with 1 card just to get Ubuntu installed and have it setup before dumping 5 more cards on to it.

I'm running into a problem with my GA-990FXA-UD5 motherboard. I know the Sempron 145 CPUs are supposed to have a locked second core which is easily enabled by swapping out a setting in the BIOS to check for hidden locked cores on the chips. I enabled the setting and rebooted and after that the system just goes through endless reboots after always trying to get back into the BIOS settings on its own. It takes clearing the CMOS to get it to stop doing it.

I don't necessarily -NEED- the second core, but I would like to unlock it and have the system work if at all possible. I'm using the latest version of the BIOS already. Any tips or other settings I need to change? The manual doesn't show needing to do anything else. If I can't figure it out tomorrow, then I'm just going to leave it as is. I just like the idea of a free 2nd core. (:

-Moose

Why would you want a second core? It's only using extra power and doesn't add anything to mining.
I always underclock, undervolt and disable cores (if possible) on all rigs I have.

My AMD X6 1055T 2.8GHz is running at 0.9 Vcore and 5x multiplier (1000MHz) for less power consumption.

[cptmooseinc]

I thought it might need the help with 6 GPUs running on one board. I did disable the onboard audio already though. If I get the system running and see it not using much CPU, I may just do as you suggested. (:

[Ryu.Hayabusa]

Those cores are locked because (afaik, this is how it was explained to me) those cores are either bad, or it was cheaper to just lock one core and rebadge it to a lower version, so its like a lottery core.

For thermal paste I would recommend Prolimatech PK-3, long lasting, great thermal conductivity, not electrically conductive, and I have been using PK-1 for years now (PK-3 is the latest product, PK-2 is an adhesive version).  I'd also suggest using it or whatever you decide on for the GPUs as well. 
PK-3 Review: http://pro-clockers.com/thermalcompound/2393-prolimatech-pk-2-and-pk-3-thermal-paste.html?start=3

+1 for Sapphire!

@zif33rs: Thanks for posting the result of the A10-5800k, I was considering this for a rig and that extra 150 sold me on it.