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Bitcoin => Mining support => Topic started by: zac123 on June 13, 2019, 06:48:04 AM



Title: Avalon 741 keeps needing a reboot
Post by: zac123 on June 13, 2019, 06:48:04 AM
hi all,
I've had an avalon 741 running for a long time now without any problems. I had a few power cuts recently, one after another because the sub station was having issues for my road.

Because of the power cuts this seemed to corrupt the sd card in the controller and i had to buy a new one. I re flashed the OS onto the card just like normal.

But ever since then my asic stops showing up on the pool. when i login to the controller via a browser i can see the OS is still running but its not connected to the pool and obviously its not hashing either. I perform a reboot and it all starts working again straight away.

it does this every couple of days.

any ideas guys?
thanks
zac


Title: Re: Avalon 741 keeps needing a reboot
Post by: DaveF on June 13, 2019, 12:21:41 PM
Could be in addition to the SD card going bad the RPi controller or the power supply also took a hit.
Do you have spares that you can test with?


-Dave


Title: Re: Avalon 741 keeps needing a reboot
Post by: zac123 on June 13, 2019, 12:23:38 PM
hmm yes that true. i have Rpi controller somewhere i could try...  i doubt ive got a psu :-(


Title: Re: Avalon 741 keeps needing a reboot
Post by: DaveF on June 22, 2019, 12:14:15 AM
It's been a week. Any luck with it?
Although, totally honestly at this point is it even worth putting time and money into a 741?

-Dave


Title: Re: Avalon 741 keeps needing a reboot
Post by: Raymond_B on June 22, 2019, 12:20:40 AM
Now that it is summer where I am and temps are going up I've lost a controller board and a PSU. So it's always possible you have a power supply going bad, I had a miner (I have S9s) constantly rebooting. I swapped PSUs and all good. So something to think about.

As far as the 741, yeah I am going to use mine as a solo miner/heater. You can down-clock them pretty good :)


Title: Re: Avalon 741 keeps needing a reboot
Post by: mikeywith on June 23, 2019, 08:17:41 AM
Could be in addition to the SD card going bad the RPi controller or the power supply also took a hit.

The probability of this thing happening is very low,even the damage of the SD card is probably just a perfect timing of misery , I know this because I had the same issues with power cuts, voltage drop below 100v on a 220v line, voltage surges above 260v , it's almost always the PSU would be the thing that takes the hit.

it's very unlikely the issue will pass on to other components, unless of course the PSU is lousy.

OP , are you getting the proper voltage after the problem with the sub-station ? I am leaning towards a PSU , before you waste your time , try a different PSU.


Title: Re: Avalon 741 keeps needing a reboot
Post by: zac123 on June 25, 2019, 11:25:00 AM
Hello everyone,

yep looks like its the PSU on the way out. I swapped the PSU from another machine and it stays alive. problem is i need that PSU on the other machine. dont really want to pay out for another one.
I already had ROI on this asic so perhaps it's time to say bye bye? :-(

although these aren't bad:

https://www.cryptouniverse.at/shop/mining-netzteil-mining-power-supply-unit-1600watt-refurbished/


Title: Re: Avalon 741 keeps needing a reboot
Post by: DaveF on June 25, 2019, 11:46:52 AM
Since it is 3 gens out it's probably time to say bye bye.

If you have free power then, you can always get the new a PSU and move it to a new miner when you get one. But to spend money now to keep an old miner running that will loose money is not worth it in my opinion.

IIRC you can also pull the cable from one of the boards and and run it as 1/2 a miner. If you PSU is marginal it might have enough to keep running @ 1/2 speed.

-Dave