Circuit requirement best practices


I have an electrical amperage question.

How many 6 rx480 8gb machines with celeron processors, 8 gb ram sticks and ssd drives can a 15amp circuit safely support?

How many 6 rx480 8gb machines with celeron processors, 8 gb ram sticks and ssd drives can a 20 amp circuit safely support?

What is the best battery backup solution for 6 machines to prevent brownout power losses?

Also, if it is not to much to ask, how many of you run 1 psu, 6 card machines and how many of you run 2 psu, 6 card machines?

What psu do you recommend for a single?

What psu do you recommend for a double?


Just glancing at this article when I googled : “how much power does rx 480 consume”

It’s roughly 168watts per rx480.

168watts X 6 = 1008 watts…

I use an Intel G3258… which has a TDP of 53 watts (Celerons are in the same ball park, 40-53 watts).

I’d say it’s safe to say that you’d need at least 1200watts, maybe even more for overhead.

I went on newegg and looked for highly reviewed PSU’s and also did some more research on JohnnyGuru(great site for PSU reviews) and I ended up choosing an EVGA Supernova G2 1000 watt(that fits my needs, I have 3x R9 Fury’s), plus I have a 620watt Antec from my old computer that I’m salvaging.

I personally plan on going with a 2 PSU setup. 1 for the board and 1 GPU, the other GPU’s I plan on hooking up to the EVGA and doing the grounding wire trick to keep it on… (word of caution/disclaimer: always do your research! always make your own decisions!)

Hope the info helps!


P.S. as for amperage… there was another site that did a conversion… on how much amps you can run through a socket before tripping the breaker(err… don’t have the link at the moment)… it’s probably best to use a 2 PSU setup(make sure you know what you’re doing) to divide the load onto different sockets that run on different circuits, that seems ideal…but to each their own.


Thank you for checking in on the subject.

It seems so much easier to use 1 psu, but I see much talk of using 2. Before I understood the concept of using 2 psu I was looking at buying one of these. They even are discounted for the holiday.

The number 1 thing I am trying to figure out is amperage draw per machine. I don’t really see any talk about that or any calculators that factor that into any equation.

I need to figure out some way to determine if a 15 amp breaker can sustain a 18 machine with 6 cards rack without tripping it for long periods of time.

Where are you based? In North America you will have 120V at home versus 240V in Europe. All you need to know then is that power = voltage x current so on a 110V circuit with 120V electricity for a 15 amp fuse you can sustain at most 1800W.

Realistically you’ll only be able to run one 6x480 rig per circuit.

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Thank you for responding garethtdavies!

I am in the US. Wow these rigs sure suck down the juice.

Once again thank you for sharing your information with me. From what you posted I did some queries on a search engine and found this discussion on bitcointalk

It has a link to this page which I found most informative.

Basically my dream of building a 36 machine with 6 cards each farm in a residential setting with a 200amp service has come crashing down!!!

If I got a handle on this properly then I think I could turn 1 240v 50amp breaker into 5 120v 20amp breakers.

So 4 240v 50amp breakers split into 20 20amp circuits could run 20 machines on a 200 amp service, which would not allow any other electricity to be used on the service and be stable!?

I am having trouble with this, am I understanding this correctly?

If this is correct then I could most likely use 100amps stepped down for mining and 100amps for the househould which equates to 10 machines stable and the ability to turn on lights and watch tv lol!?

36 rigs would draw at least a continuous 40kW which is a lot of power! Have you calculated the electricity bill for that?

Either way that’s not feasible. There is another thread here about mining at scale Physically locating GPU Servers at Massive Scale - #10

If you are serious about modifying your home electrical system I’d highly recommend you get an electrician to look at your individual case. You can let a lot of information looking at your fuse box but the article you linked to mentions the dryer circuit which has a special outlet and you’ll only have one of those.

Running 10 at home is likely possible depending on the number of circuits you have if you can spread them to every room but don’t underestimate the heat and noise asssociated with all these machines (though the RX 480s are very quiet).

are you in a house? you actually have quite a few options that most people don’t think about.

For example my apartment comes with 2 40 amp circuits. People don’t think about them because they are used to run the dryer and the electric stove. They are 240V AC. With those circuits you can run a max of 9600w off those. All you would have to do is switch your computer PSUs connected to the circuit to the 240V setting and make a custom plug strip that connects to the dryer plug and splits out to 20 amp style plugs(the one where one prong is up and down like normal and the other is horizontal(turned 90 degrees) so that you don’t accidentally plug something like a hair dryer or some normal electronic into it as it will instantly fry.

So you can run one miner per 115v 15 amp circuit. I currently have 1 miner running and the 15 amp circuit runs warm on the verge of popping. I run a BTC board with 6 x RX480’s and my real time watt meter says 1229 watts steady
The question is: are you looking to expand? What is your goal of expansion? can you access a 220 outlet anywhere in your home?

If you are in a house generally main power comes in by the garage area. It wouldn’t be difficult to take off of main power and make a second fuse box for just your mining circuits and run then in the garage.

I think the reason is most people want to use the dryer and electrical stove :slight_smile: And definitely no to the hairdryer or popcorn machine!

I mean you don’t have to not use your dryer or stove but you aren’t using your dryer or stove 100% of the time 24/7. so you can use them if you do it correctly. :smiley:

A good rule of thumb is to only consume 80% of a circuit. This is to allow in-rush when you power off or on device on the circuit preventing the circuit from popping. A typical US home is 110v for a 15A circuit. 110v * 15A - 20% = 1,320W

Now to how many RX480 depends on the software and how well utilized the cards are. From some research it looks like Claymore is pushing a stock rx480 at around 115W.

6 x rx480 (115w) = 690W
TDP of recent celeron = 35W
SSD = 10W
Motherboard = 25W-E??

So maybe 750W for a single 6 card RX480 system? You’ll also pull more at the wall due the conversion of AC → DC of the power supply. To really get an accurate reading you should get a WeMo Insight Switch or a PDU that shows your draw to really understand your power usage. At the numbers I came up with, you might be able to get two rigs on a single 110v 15A circuit, you’ll slightly be over 80% but should be fine. If the software can get more out of the cards, increasing utilization/increasing watt usage, the 100v 20A circuit would be a safest bet for 2 rigs.

Hi everybody!

I appreciate all the feedback and discussion.

I have been unable to get to my pc for a bit.

Basically, I have a couple people that would like to pool resources with me and put together 3 metal home depot racks with 12 open chassis on each rack that all have 6 rx480 8gb cards running windows 7 with claymore.

Electricity has always been a mystery to me, but, I put on my thinking cap and think I understand the 240v to 120v step down concept.

I guess I need to get a proper rig up and running while figuring out how to scale.

The machine that I built was all wrong because I was clueless about the cryptocurrency space and how I interpreted the way to get mining. The specs are as follows.

Board: Gigabyte Z170-HD3
CPU: i7-6700k
RAM: Crucial Ballistix 64gb kit
SSD: 2 OCZ TR150 120gb in RAID 1
PS: EVGA 750 BQ Bronze
Case: Piece of junk

I added these after cpu solo mining on linux for a week or so and getting no where fast.
GPU: 2 XFX RX480 8gb

Hell I was a babe in the woods at the beginning of all this with no experience.

I see that people tend to favor sapphire cards which is all good, but I need to buy 216 and trying to find that many of them ain’t easy. seemed the best shot for pricing but they will only do 10 at a time to keep re-sellers away.

So after learning a bunch a bought 2 asrock H81 PRO R2.0

And instead of buying a open chassis pre-built like I saw and was tempted to buy from ebay I decided I would follow this handy dandy guide I stumbled across here.

Anyway, I plan on figuring out how to scale the machines after I build a couple test ones after the new year as well as figure out where in the heck to put them.

I am open to collaboration on building a farm team farm lol pun intended and need all the help I can get understanding how to get all machines not to catch on fire or trip the breaker as soon I turn them on.

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If you are going to run more than just a few rigs, you should definitely consider running them on 240V. Drawing 20A at 240V delivers the same amount of power as 40A at 120V. Less current also means cheaper and thinner wires (much easier to work with)…

Hi everybody!

I am very close to securing a space that has agreed to let me have 3 240v 50 amp circuits and 2 20 amp circuits for 1 thousand us a month utilities included.

Will this be enough juice to run 216 RX480 8GB cards?

Can anyone tell me how much there 6 RX480 8gb machines are drawing at the wall?

About 850 watts.

You might want to consider walking before you run. If you have not built at least one rig that you can profile and understand how to maintain, you’re getting ahead of yourself by drawing up plans for running 216 GPUs.

I rented a very similar size space to that. It has a 240VAC 200 amp rated circuit, but at 160 amps the main breaker trips. Anytime an electrician quotes a number, plan on using 80% of that number. Right now I am running half Antminer S9s and half GPU miners with RX480’s in the space.

The 6 GPU RX480 rigs are using about 4-5 amps at 240VAC mining ethereum. I use a single Antec 1300 Watt Platinum PSU and it works fine. I have 6 30 amp 240VAC receptacles powering 6 30 amp Tripp Lite PDU’s. While doing this I wrote a planning guide. I also wrote a guide on building a 6 rig Zcash miner with R9 Fury’s, but those pull 7 amps at 240VAC, so I’d say stick with the RX480’s.

You are going to want to use natural circulation cooling. At my space I have a garage door, and put a vent in one half, a 10,000 CFM fan in the other, and built some drywall to direct the airflow through the miners. Here’s the writeup:

here’s a picture of my wooden frames in home depot racks!

But I think you are better off with the $117 aluminum frame from parallelminer

blockops, you are a superstar! I am real far away from home and will be for a lil while but, I can’t wait to get started when I get back.

My buddy and I started to build a wooden rack with a basic design from highoncoins I took off before we could finish it but he completed our solo.

Swimming in the ocean in January is much more fun then sliding off the road in freezing rain imo.

I think I am going to make a open market purchase on this pullback.

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