Topic: Two different psu? (Read 214 times)

1. To connect multiple PSU’s to a motherboard (which is not meant for that), you will need an adapter similar to this https://www.ebay.com/itm/New-Multi-Power-Supply-Adapter-Connector-ADD2PSU-PSU-board-For-Miner-ETH-BTC/292195480750?epid=22006161000&hash=item44083534ae:g:RsgAAOSw7ChZeB01
Connect power output from one PSU (the one connected to the motherboard) to the adaper and plug in the second PSU with its standard 24-pin output to the adapter.

As soon as masterblock is switched on, the second power block will run by itself from the adapter.

Important: Do not run an unloaded power supply (connect at least a fan to it)

2. It is important to remember that when you connect GPUs to two different PSUS,  they should not be cross-connected. Which means, if GPUs are fed through the riser to one block, don’t feed them through the pci-e power cable to the other.
That can lead to a poor performance of a motherboard.

3. If PSUs are purchased and the pci-e power cables are too short, you can use something like this https://www.ebay.com/itm/PCI-E-PCI-Express-6P-Male-to-6Pin-Male-Graphics-Power-Cable-Extended-Miner-Wire/282771015240?epid=908915615&hash=item41d6774648:g:S5kAAOSwkLhaMNOf

4. I wouldn’t recommend to use noname Chinese PSUs, which promise you 1500+W for 50$. In general, this product has poor quality and can damage your rig. It’s worse looking towards known/proven or local brands, which will be promptly repaired or replaced if a warranty case occurs.

5. From a technical point, PSU should be selected based on 3 general criteria: 
- General power on a 12v bus: If you plan to use it 24/7, consider, that manufacturers do not recommend to load PSUs more than 80-85% of the announced power load
- I recommend looking towards efficient PSUs at least Bronze. At 24/7 and long term operation, you will gain in a lower energy consumption and lower PSU heat dissipation
- I suggest modular PSUs. They are often not much more expensive than conventional PSUs, but are much easier to operate and if you use the same power blocks in your farm, they can be replaced promptly.

I've used 2 PSUs since the LTC mining days of 2013-2014 and never had an issue. I didn't even use the ADD2PSU adapter I just used a paper clip.

All you need to make sure is not to mix the +12V between the PSUs. So don't connect one +12V from one PSU into the same GPU using another +12V from the other PSU. Since the voltage is never equal and it will make current flow from one PSU to the other and burn it up.

Both PSUs should be grounded however, so you can just make a little connection between the GND from both PSUs.

Another issue is make sure the aux PSU always has a load running incase the main PSU is shut off during a system shutdown. So attach a small fan or some other accessory so the PSU doesn't run on no load which could damage it.

Sometimes Server PSUs are simply not enough to run high-end mining rigs. A rig composed of 1080tis will have a hard time being powered even with a 2kw server PSU.

So when it comes down to it, Add2PSU is a good option, but a better potion would be to use a mother board that supports multiple PSUs. An example of such motherboard would be the ASUS B250 Mining Expert which is capable of supporting up to 3 PSUs.

Ok and do I have to use the exact same ones or can I use for example the I already have with a 700W be quiet! one?

it may be.
almost all my rigs use two PSUs and combine them with two different brands so far functioning smoothly. I use add2PSU or use a paperclip.

Nice setup Bro

just like to ask how's the server psu noise? are they not get wild while mining?

I am planning on converting my other rigs on these this kind of setups

Dont waste y our time with an Add2PSU or other nonsense. Get a plain old server PSU like one of these (they accept crypto): https://www.parallelminer.com/product-category/power-supply-kit/

I've been running thirty RX 580's with a four 850W EVGA PSUs and four 1200w server PSUs, the server PSU powering all the GPUs and the EVGA powering all components and risers. Been running 18 months with zero issues.

You can use Add2PSU adapter for starting more than 1 PSU when you boot up your mining rig. Really great little adapter that can help you to multiply your much-needed PCIE connectors.

Which mobo are you using?
Are you referring to the 4pin using on riser or gpu itself?  For riser you can use sata / 4 pin extension but never plug in more than 2 risers for each cable. 

Hey guys,

is it possible to connect two different psu to the motherboard?
Im currently using a 1200 Watt be quiet! Dark Power Pro 11.. If so, do you have any recommendation?
Are there also PSU with long VGA cables (I mean the power supply for every gpu, 4pin)? Because the bequiet has only small ones and its pretty hard to connect many gpus with that little moving possibility...

Thanks in advance!