Backwards on AMD/NV.  Nvidia cards are significantly more versatile.  AMDs are mainly just cheaper.

I'd probably spend half the money on used, cheap AMD RX 4/570s & bitmain S9s first, and the rest on newer tech (gtx 16xx, Vega VII, etc) when they arent selling at such a premium.

Also: 7% fixed rate on a liquid account?  My life would be so much simpler if those actually existed.

Depends on your situation, strategy, and cash flow I'd imagine.  I can give you a few reasons I split my farm up.

1)  I have several different rig configurations (RX rigs, Vega, GTX 60/70/80, etc), and they all perform a bit differently on different algos.  So I try to keep them pointed where they perform the best/better, for the most part.

2)  We dont take profits short term at all.  Other than my time keeping everything running, we have zero overhead...and the time I spend on it I dont put a whole lot of value in.  It's not that I dont value my time, I do...but it's mostly just time I would otherwise be spending playing video games or a round of golf or something, so it's a value add instead of a value negative.  As such, our time horizon is medium to long term hold, so I'm not overly concerned about short term profitibility.   Mainly we want our BTC/ETH bags to grow, and have zero time/desire to day/swing trade coins on exchanges.   Essentially we are using hash power to dollar cost average in directly to a specific portfolio allocation.  For the most part, we only use the coins to buy parts (build/upgrade rigs, replace dead fans/risers/etc).

3)  Taking a few swings at newer algos when they first release, and the difficulty is low.  Like I said in a previous post, we dont do a whole lot of this...mainly just let software auto switch on it's own.  I'd guess, on average, about 20% of total hashing power spends about a week or so a month on something speculative.  Now that I type this out and read what I'm saying, I probably need to do a better job of tracking this...

Anyway, I doubt what I'm doing is "right".  I'm quite sure there are better ways to go about doing it....but considering the resources we have available, the professional & practical limitations we have as a group, and our longer term goal this is what is working.  Currently.  I reserve the right to change my mind.

I'm not 100% on ethash, nor am I ever 100% uptime on all rigs/gpus, but if I were I'd be around ~3200-3400 MH/s total.  AMD rigs = ~1100 MH/s stays on ethash (ETH & ETC), ~ 18 kH/s on CNR (Monero).  NVIDIA Rigs I mostly leave on YIMP pools/MPH for BTC payouts, a couple stay on RVN.  I try to put a few rigs on new coins/algs early, but dont really spend a whole lot of time researching them so I dont catch as many of those as I probably should. 

Not if he builds a Vega Rig...no hurdles there at all!



 

20 4x to 8x GPU rigs.  2 ASICs. 

The ASICs are no fun at all....they just run.  I wont be buying any more of them.  The GPU rigs though, there's always something going wrong with one of them that I have to diagnose & fix...generally speaking, 19 are running and one is on the bench at all times.  I'm building more of those.

Free/cheap power certainly makes everything a whole lot easier. 

Mining can make sense on a really micro scale (i.e. running cudo on your gaming rig when you arent using it, putting a rig or two in your garage/dorm room, etc), and on a really macro scale (gigantic farm in some area with cheap power, cheap space, and cheaper labor).  In between those the economies of scale bite you.  It's tough to make it work, the margin is too tight to add any additional overhead costs (rent, labor, etc). 

Technically speaking, I've not seen ROI on my first rig because I never paid myself back for it.  It did buy a second rig, though, then those bought a 3rd...then a 4th...etc etc.  Will I ever ROI?  Hell if I know.  Essentially all I'm doing now is dollar cost averaging large cap coins AND hash power at a discount, with a medium to long term time horizon.  No idea if that's the best way to go about doing things.  Probably isnt.  Truth be told, I just enjoy building & tinkering with the rigs more than anything. 

The OP asked if it was a good idea to invest in a mining rig.  Maybe it is, maybe it isnt...I was really just trying to help him answer that question for himself as I can't answer it for him.   

AMD rigs mostly divided up between Ethereum and Monero, occasionally I'll drop a few of them on a new coin.  NVidia rigs I pretty much just leave autoswitching on YIMP pools for BTC payouts.  I'm building a new rig about every 2 months using some of the BTC to buy parts...basically I just troll ebay for cheap cards & various parts daily, and eventually a new rig appears.

Power isnt free, but I have 120 amps that's heavily subsidized.  Have a friend with industrial power at his business...he eats the electical cost & cleared out space, and gets 25% of the coins mined.  I have a few rigs and a couple Z9 minis at the house, and I just eat the power cost on those.

I'd imagine the youtube video of the guy making > 1.00 per day on a 1060 is rather old, or he's valuating his average per day based on what he gets when he converts the obscure spec coin he's mined at an opportune time later on when it lists and pumps.  If you are just going to mine on it when you arent using it (turning on a miner when you are away, using cudominer to start up when its idle, etc) you wont be getting the .27 either. 

Is it worth buying a mining rig now?  I'm still building more of them, so for me the answer is yes.  Your answer may be different.

1) Do you believe in the big-picture idea of cryptocurrency?  If yes, maybe.  If no, probably not.

2)  Are you financially able to withstand the build out costs, maintenance costs (shit breaks), and electrical costs without taking immediate profits?  If yes, maybe.  If no, probably not.

3)  Time: Do you enjoy tinkering with computers?  And by "tinkering" I really mean regularly diagnosing why _insert_something_here_ suddenly stopped working?  If yes, maybe.  If no, probably not.

Finally, assuming you made it this far having answered yes to the above: 4)  Is it for some reason (be it personal, professional, or regulatory/whatever) more convenient for you to mine coins rather than start dollar cost averaging in by just buying the coins directly?  If yes, then absolutely.  If no, then...maybe.

1)  yeah.  I dumped it for zpool several months ago.

2)  Dont know, depends on the alg.  I'd imagine if the alg your asic runs is supported on the site, it'll work...but havent ever played with it.   I just have a couple of Z9 minis and a bunch of gpus, and at this point I just leave the Z9s on Nicehash and forget about them altogether.    If you cant get your asic to run on blockmasters, try zpool, zergpool, blazepool, hash refinery, etc. 

3)  Use your bitcoin (or litecoin, doge) address as your username.  If you want to mine to a multi alg pool and exchange (payout) in a different alt, try miningpoolhub.

4) yw

increase your virtual memory to the 32000 range

It's a great time!  Want to buy one of my rigs?  /joke

Buy the dip, sell the rip.  I wouldnt be so sure the prices have stabilized yet.  I'm keeping my farm running now only because power costs arent an issue.  As tempting as it is right now to buy into some more hardware at significantly lower costs, I'm waiting for confirmation that the bottom is in.  GPUs need altcoins to mine, how that market shakes out...what happens to prices in the alts, difficulties in the algos, which projects/algos can survive a $3000 btc/ $50.00 eth environment, etc...will effect what hardware I want to be running in the future.  It's not just ASIC vs GPU...you have to consider specific ASICs and specific GPUs...along with possibly FPGA. 

I do think the prices are pretty good to start thinking about buying in, though.  Just understand there is a significant chance the bottom isnt in on the market yet (IMO, I think BTC into the 3000s and another 8 to 12 months of a bear are likely), which means even at the current prices ROI on new equipment purchases is going to be a while. 

If I were building a new rig right now, I'd probably go with 1070s or 1080s...MAYBE vega if I were going AMD and wanted to ride cryptonight.  If you can find some 6gb samsung 1060s, that would be good for what you are looking to do (speculative mining) as well, lower price point.

If you have free power, you will probably ROI quicker buying used ASICs on Ebay (s9, l3+, etc).  If you dont, avoid.

If you have decided on GPUs, I'd strongly encourage NVidia over AMD.  What shield132 said above is correct: just more efficient and versatile than AMD cards, and I wouldnt count on mining Ethash for much longer.  Besides, AMD cards are always ... in my experience... a lot of tinkering time.  I have 3 AMD rigs, and 3 Nvidia rigs.  The Nvidia rigs I basically never have to mess with except to do routine maintenence (cleaning dust, etc).  The AMD rigs though, I have to reinstall something on them every few weeks.  If anything ever breaks, it's on an AMD rig.  Mainly I dont mind that because tinkering with the rigs is something I actually enjoy doing...but just know what you are getting into.

My results are largely anecdotal estimates, as I mine more or less as just a hobby.   My equipment has ROI'd, and I have a deal set up at an industrial site where I pretty much just give up 1/4 of gross revenue as "rent" for the room & power (so I dont take power costs into account in any way).  I mine & hold, all I ever cash in is to pay for equipment maintenance (replace a dead gpu, fans, etc).  As it's just a hobby for me and I really dont want to invest any more time into it than maintaining the farm remotely while I do my day job, and going by once a week for maintenence on the rigs.  I dont want to hold every speculative coin imaginable, and am not extremely concerned about making sure my rigs are running at their absolute best on the most 100% optimal algo 100% of the time....though I'd like for them to run pretty well, and get good results with what they mine.  I use Awesome Miner on Windows, and have all available pools set up except for Mining Dutch (I have no idea why I've never gotten around to using this pool) and have a manual pool set up to mine a few specific coins.  I could probably get much more efficient results manually pointing my rigs to specific coins then trading them myself or holding them, but I dont want to spend the time doing it. My GPUs are probably not set up with the most efficient settings possible, but I have tweaked them to get pretty "standard" mining performance for each algo, and they swap settings automatically through awesome miner & Afterburner as they change algos.  I spent a good bit of time getting everything tweaked on the front end so that I could run it as automated as possible.

Here's what I'm running that way, and my experience on their results:

1 6x 3gb 1060 rig:  Spends 80% of it's time on Blockmasters & Zergpool*,  the rest of the time occasionally bouncing between HashRefinery, Blazepool and Nicehash.  mostly mines Lyra algos but occasionally Phi, X16r/s, etc.  Currently grossing around 2.45 USD (actual results) per day

2 6x 6gb 1060 rig:  Similar results to the 3gb rigs, but goes to ethash on MPH maybe 10% of the time.  Grosses about the same as the 3gb rigs, around 2.60/day currently

3 8x 1070 rig:  Spends a little more time on ethash (bouncing between MPH and Nicehash) than the 1060 6x rig, but not by a whole lot.  Maybe 15, 20% of the time.  Grossing around 5.50 per day currently.
  
4 7x rx 480 rig
5 6x rx 580 rig
6 6x rx 570 rig
7 2x rx rig (spare parts, more or less):  These all do the same thing: Mine Ethash all day, 90% of the time on MPH.  Occasionally swap over to Nicehash, but rarely.  The 6x rigs are doing around 2.75, the 7x around 3.  Dont really pay attention to what the 2x rig is doing, to be honest.  I havent gotten around to bios modding those cards yet (which would have probably been a better use of my time than writing this post, but I'm lazy)

8 2x 1080 rig:  Always on Ethash MPH when it's mining.  Regular 1080s, not TIs.  Running Ethlargement.  Not real sure what this one grosses as it's my personal computer, and probably only mines about half the day.

9 2x z9 minis: 100% of the time on MPH.  One runs stable at 15k, the other runs sorta stable at 13.5-14.  Both grossing 4.7 to 6 per day, currently.  Doubt these ROI.


*Zergpool just shut down for good, so I imagine I'll be on Blockmasters most of the time on the Nvidia rigs now.

With the current difficulty/price of ethash coins being what it is, my Nvidia cards stay away from it for the most part.  My AMDs still stay on it.  Kinda curious what will happen going forward as we exit the bear market over the next few months, but considering Eth is dropping mining rewards per block by 1/3 soon I dont imagine the NVIdia rigs will spend much time on it.  The AMDs...I wouldnt build any GPU rig right now unless I got one HELL of a deal on parts...but I certainly wouldnt build an AMD RX rig now.  If I found some dirt cheap Vegas, maybe.  

Anyway like I said, mostly anecdotal but I hope that helps.

Short version: plug your  MPH account info & your bitcoin address into zergpool, AHash, zerg, Nicehash, blaze etc into the proper boxes on the profit switching tab.  Then benchmark all.  Then press go and let awesome miner do it's thing.  Pay attention to what it's doing for a few weeks, you'll figure it out as you go.

Long version: read through awesome miner's webpage.  Search youtube for Goose-Tech and DaveTech CA, they have some good instructional vids on awesome miner

I got 4 mini's in Tuesday 9/4. All of them had the newer firmware where only 'balanced' was shown. I downloaded the firmware from bitmain (only one available) an applied to one miner. Once all seemed well I applied to the other three.  I set them all to 650 freq with auto fan. Temps are in the high 60's for the hash boards. Averaging 14.5 hash per miner. All four have been running now for over 48 hours with no problems. I'm mining ZEC on Flypool.


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I got two on the same date, have them at 662 avg 14.8.