Topic: LightningAsic usb miners based Gridseed GC3355 Tech Support Thread - page 31. (Read 73479 times)

900x350x500 mm

nice!
What are the dimensions?

I had Jack's tech log in and turn it off.

Cool ! But you may have some difficulty with the 40 wires and connectors (takes place), and you need 4 PSU and 2 hubs.
If you do LTC only then one psu would be enough, and I guess you can remove all the fans.

We are mining dual mode for now. After next two diff bump I'll probably switch to scrypt only.

Here is that 2u L case I was talking about, 20 orbs should fit. The paper circles are 4 inch. specs say the real thing is 3.75.
I was going to take off fans and maybe put 2 intake 80mm in front and another 2 in the rear.
-Bobby

Looks great!
Are you doing BTC/LTC now or just LTC?
-bobby

Looks nice, simple but usefull solution! 

Here is our LA6M rig.
1200W, ~180Ghs, ~6Mhs
Reboot every 30/40 minutes...



Full gallery
http://imgur.com/a/hMzG0

I'll remove the fans and put 20 in a XL 2U case. Keep the heatsinks on them. Exhaust the box with 2 80mm fans.
-bobby

That was also my thought, but I must wait until I get the miner to can measure the temps and more to decide, what I want do.

Can someone measure the height of the unit without the fan?
Thanks ahead!!
-Bobby

If you were using the gridseed cpuminer git repos you should edit the source to have it print on read timeouts (https://github.com/gridseed/cpuminer/blob/master/gc3355.h#L288).  When I attempted to hook up my units to a linux box they looked like they were getting work from the normal output but in the end the code was just hitting this read timeout over and over again.

Anyone know how to fix the 10 minute restart issue.  Someone earlier mentioned they had a problem where the units would shutdown in 10 minutes if one of them wasn't hashing.  Seem like the timeout is too low as mine are stuck doing this now and I'm at work so can't restart them and bring them up one at a time.

...
[2014-02-21 15:52:54] LTC process startup: Bus=1:5 Pid=1000 Worker=gigq.light1 Frequency=850
[2014-02-21 15:52:54] LTC process startup: Bus=1:6 Pid=1013 Worker=gigq.light1 Frequency=850
[2014-02-21 15:52:54] LTC process startup: Bus=1:7 Pid=1026 Worker=gigq.light1 Frequency=850
[2014-02-21 15:52:55] LTC process startup: Bus=1:8 Pid=1034 Worker=gigq.light1 Frequency=850
[2014-02-21 16:02:54] Device downtime (LTC): DiedBus=1:11,1:13,1:3,1:4
[2014-02-21 16:02:54] All process shutdown - dual 3
[2014-02-21 16:02:54] Close the USB controller power
[2014-02-21 16:02:55] Open the USB controller power
[2014-02-21 16:03:21] BTC process startup: Pid=3479 Worker=gigq.light1 Frequency=850 Devices=0,1,2,3,4,5,6,7,8,9 Bus=1:10,1:11,1:12,1:13,1:3,1:4,1:5,1:6,1:7,1:8
[2014-02-21 16:03:21] LTC process startup: Bus=1:10 Pid=3534 Worker=gigq.light1 Frequency=850
[2014-02-21 16:03:21] LTC process startup: Bus=1:11 Pid=3547 Worker=gigq.light1 Frequency=850
[2014-02-21 16:03:22] LTC process startup: Bus=1:12 Pid=3560 Worker=gigq.light1 Frequency=850
[2014-02-21 16:03:22] LTC process startup: Bus=1:13 Pid=3573 Worker=gigq.light1 Frequency=850
...

Graph of what this does to my hash rate, you can see it drop back down every 10 minutes or so and not be able to work it's way out on its own.

https://dl.dropboxusercontent.com/u/117000/scryptminer/hashgraph.png

750 MHz seems to work best for me so far... anything over that and I lose about 30% of my hashrate.

We were thinking of removing all radiators and fans, and put 20 IC in the box with some kind of giant aluminium radiator + paste on the top.
First we need to check what is the temp of chips in LTC mode only ; if it's 2W / chip I'm not sure we'd even need radiators.

How did you get dual mode enabled.  I thought the controller that came with the box didn't support it.


True, the difficulty is going up quick which is why I was hoping to get some btc mining out of it before it wouldn't justify the electricity cost.

Make sure you get a 2U XL box, 20 will not fit in a normal 2U box. I have a 2U L box coming on monday thats 25 1/2 long.
I made 20 3.75 circles with cardboard as a test and they did not fit in a standard 2U box that I have sitting here.
-Bobby

DUAL MODE
With a core frequency of 750MHz, I'm finally able to have 95Ghs and 3000Khs.
I didn't change anything, so I don't know why before I had very bad perfs. Maybe it's just random and after a lot of plug/unplug it just stabilized to something.
Power draw is ~600W including everything

LTC MODE ONLY
Impossible to get over 3000khs, whatever the core frequency. Maybe it's related to the fact I'm hashing on a coin switching pool.
EDIT: with wemineltc pool (LTC coin), I manage to get closer to 3500khs ; but it could be inconclusive
Power draw is ~100W including everything

NOISE
It make some noise because of the ventilation. With 10 units, it's supportable, but for instance you can't make a Skype handsfree call.
Also, it generates a lot of wind, and if you have papers nearby they'll constantly move.

LINUX BOX
We successfuly connected one unit to a linux box, and we are running a version of CPU Miner.
It gets work and I think it's hashing, but we have some problem to submit the shares, so for now it's not conclusive.

FORM FACTOR
In 2 weeks, the BTC mode won't really justify itself so we'll be in LTC mode only. We plan to remove all fans and put 20 units in a 2U box.
We'll test how chips are supporting heating, radiator only should be more than enough.

So, single scrypt mode is default with cpuminer? That would be great (since I plan on only using dual mode sometimes).


Anyone who can comment on how noisy they are?