Is it just a switch or a router? I have had problems with the Dlink QoS settings in the router. That would be my only suggestion, a dumb switch should have no problems with the loads you are running.

I dont personally make wallet recommendations but there is more than enough information available that will help you decide.

As far as the pool goes you basically have to run it on a pool or you are throwing away money at a lottery ticket. The network is so big and it is dominated by large pools. The chance of hitting a solo block is pretty negligible.

If it will not respond to any inputs most likely the beagle bone is dead. There is not much you can do to repair them.

It sounds like the person you bought them from had a crazy overclock running. Its no surprise that one of your boards has failed. You should never overclock this stuff, its just asking for failure.

You will not be able to buy a 'new' replacement hashing boards specific to the LN as the S7-LN wes a 1 off production run over a year and a half ago.

Please post the actual miner info page. The awesomeminer status page is totally useless. I cant even determine what type of miner you have from the information supplied.

Get it hashing and take a screenshot of the miner status page while its actually reporting something and post it back on here.

The controller is set to a static IP from Avalon by default. If you are using a different IP scheme/subnet you will not find it.

Just throwing this out there....its not that hard to get a 220 circuit wired up to run a better power supply. Its not like the USA is limited to 110 power only....

Remember that the s9 board is a string design board. Any single failure point will cause it to stop working, most often this presents itself as a single bad chip. The problem with this is you cannot source brand new s9 chips to do the repairs properly.

The connectors are shared internally, it is not 1200 + 1200 as it sounds like you are wondering. Also remember the rule for power supplies, you want them at about 80% of their rated capacity. Also you might want to use slightly higher numbers when estimating power draw. Remember what a miner pulls from the PSU is not what the PSU itself is pulling at the wall. Even the bitmain sites say add 10% to the power draw when calculating it.

With that in mind I would estimate an s9 at around 1500w, and an l3 at 900w.

This is really pushing the limits of that power supply at that point since you will be at almost 100% load. I would not recommend trying to run the L3 and S9 off of this single PSU.

Temps are not a problem if the machines are running. The problem is if a machine stops hashing for any reason and the boards end up ice cold. The processing chips will RAPIDLY heat up while the rest of the board might take a bit. This temperature inequality will cause damage.

Bitcoin mining is very volatile based on a number of factors. Forecasting profitability more than a month into the future is virtually impossible. Your best bet is to make an EDUCATED guess on the difficulty changes and hope you are somewhere in the ballpark.

Also note that zcash adjusts difficulty dynamically so you may look in the morning and expect say 0.326 ZEC from your rig but by the end of the day you may only get .305. Its really hard to pin down consistent payouts with ZEC based on this so dont worry if the numbers are not the same day to day.

Just a point of clarification on your earlier question. Bitmain boards use a string design, like a set of christmas lights. When one chip dies and is no longer passing signal along its predetermined path, the whole board fails to run.

As far as the controller getting weird, the only thing you can really do is factory reset it or update the firmware in case something got corrupted.

If and only if you have truly free power would i even come close to that power hog of a card. At the price you quote it has about a 5 month ROI before you make any profits.

^^^ Found your stability problem

If you want stability, switch to linux

Have you tried to factory reset the controller? Ive had some on the antminer get lost like that and a factory restore fixed them up

the add2psu thing is just a waste of money. Just turn the PSU powering the cards on first and you will be fine. You dont need to power cycle the cards along with the motherboard either.

DO NOT ever mine on a laptop.