Post
Topic
Board Mining (Altcoins)
Re: Building Cheap Miners : My "Secret"
by
MinersRus
on 09/05/2018, 15:39:37 UTC
Just found this thread. I've got two DL580 G7's with E7-4870's. I'm currently mining with 30 GPU's on standard mobo's. Never could get GPU's to work in these. Is it still profitable to set these up and eliminate the "small" rigs? I am currently running ZEC, but would switch out to something else if profitability is there. Would definitely want to swap CPU's to 8837's.

It all depends i would say. The DL580's are power-hoggers. What is nice is H/s per $ on the initial costs, but running them worth profit requires cheap electricity since there is a lot of overhead power drain on these systems.

One easy way to save power on the DL580 G7's is only run with the minimum number of memory cartridges. Each cartridge uses 30 watts.
Also mining doesn't really need much in the amount of memory.

This is from a PM on the subject of saving power:

Quote
I have now gotten three DL580 G7's up and running with HiveOS. I am always looking for ways to save power on the DL580's and this is a way to save an addition 90 watts per system with very little hit to the processor hash rate.

From my previous post(s) I have found that each memory cartridge uses 30 watts. So the first thing I did was to remove four of the eight cartridges and have only one per processor. That saved 120 watts per system.

With further thought, since XMR-Stak running on processor cores should only use the internal L3 cache, what if I only had one cartridge on processor 0. The other processors if they need to get to memory would hop from processor to processor.

Doing that XMR Stak only took a 1-2% hit to hash rate from 1618 to 1587 on one DL580 and 1617 to 1599 on another. Booting up the DL580 with only one cartridge is fine as is booting HiveOS. The only thing you will see in the when XMR-Stak starts up that it will say "hwloc can't bind memory" but as seen above it really doesn't effect hash rates much at all.

One physical issue I need to address is that without memory cartridges installed the metal flap closes the vent to the front which does restrict air flow. I either need to remove those flaps or install a wooden spacer bar that would hold them open.


Follow-up:


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I have a solution for holding open the flaps.

I am using one of these small clips for each flap that I want to force open:

https://www.amazon.com/Staples-Metal-Binder-Clips-10667-CC/dp/B01LYTURRW

When they are attached holding the flap open flip down the metal loop on the inside of the case and on the metal loop on the outside squeeze it to remove it. Keep at least one metal loop if you want to easily remove the clip again. The metal shield over the memory and CPUs attaches fine with these clips installed and the whole processor/memory assembly fits into the unit without issue.

I now have three openings for air, one into the single memory cartridge and the other three in front of processors 2, 3 and 4.


Another solution:


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I ended up using a 2" wide piece of cardboard cut the width of the proc/mem case with 3 slots the flaps to keep them open, I also ended up with one slot open per CPU.


Final Follow-up:


Quote
In case the cardboard doesn't last I need to point out a few updates to my solution. I have only one memory cartridge installed in the top slot (I'll call it #1). The other three flaps I have open is #2, #5 and #7. The clips are also positioned to the left end of the flaps that way they don't block the 4 metal tabs on the top plate so that it can cleanly be installed. The reason I do flap #2 and not #3 is if I did #3 it does not allow the front handle to close properly. Even with not doing #3 the handle will close but not latch unless you give the blue latch some downward pressure.

Also I feel comfortable in that the clips will stay in place because of their strength and that the top metal plate holds them down.