Mining. You’re probably sick of hearing about it!  But its in the news. Its on TV shows. Its all over blogs. Well, not mining specifically, but cryptocurrency. Specifically a certain type of cryptocurrency called Bitcoin. To mine bitcoins you need an ASIC powered miner. But for many other cryptocurrencies like Ethererum can be mined with GPU cards in regular computers. It didn’t take long for people to figure out that you could put 3, 4, 6 or even 12 GPUs in a single computer using PCIe risers. This led to the need for massive power supplies in the 1500 watt range or more. That is until someone figured out a way of using dual power supplies for mining!

Running Dual Power Supplies in Mining Rigs

When you stack multiple GPUs in a mining PC you start to use a lot of power very fast! In some cases a single GPU can eat up 200 watts of electricity. However, in most mining PCs the GPUs will only use around 160 watts.  Even still, 160 watts multiplied by six is 960 watts.  Add a motherboard, risers, CPU, hard disk, networking adapter, etc. and it doesn’t take long to blow past 1100 or 1200 watts.

This can be very frustrating for new miners.  Not only can a 1200+ watt power supply be very expensive, they can also be very hard to find in-stock.  I have a list of the best power supplies for mining rigs you can read up on for more information.

Dual power supplies makes it possible to use to 750 watt supplies in place of a single 1400 watt supply, and probably will save you some money in the process.

Setting up dual power supplies is super easy, but it is risky if you don’t know what you are doing.

How to Setup Dual Power Supplies for Mining

Using dual power supplies for mining requires a special piece of hardware. There are a couple of ways to go about it though, and I’ll show you both.

Using a Splitter Cable for Dual Power Supplies

Modern ATX motherboards actually control the power supply. This feature can make it difficult for using dual power supplies. Two of the pins on the ATX power connector turn on and off the power supply.  If only one power supply is connected to the motherboard the other power supply won’t ever turn on (or even know how) when the motherboard activates the PSU power relay.

To solve for this, some really creative guys came up with an ATX power cable that splits that relay signal into to cables. Just plug both power supplies into this cable and then plug the cable into the motherboard.  This fires up both power supplies when the motherboard power button is pressed.  These are safe, reliable and a simple way to use dual power supplies.  However, be sure to read the risk section below.

You can get these splitters here!

Using a Sync Module for Dual Power Supplies (or three or more!)

Another great option that becomes exceptionally handy is a power supply sync module. The sync module works by connecting to a SATA port on your main power supply. When it senses power is applied, a relay engages the power pins on the second power supply.

This is incredibly handy for use with three or more power supplies in much larger rigs (12 GPU rigs). You can plug as many of these into your main power supply as you have SATA ports available, and then plug the rest of the power supplies into the ATX headers on the the sync modules.  Pretty sweet idea!

These modules are safe and effective, but be sure to read our risk section below before using them!

You can pick these up here for cheap!

Risks of Using Dual Power Supplies for Mining

Using dual power supplies for mining is not without some risks. But they can be completely mitigated if wire them correctly. All it takes is a little learning.

The problem is that the power between the to power supplies is not isolated. This can be very problematic for circuitry in your computer, especially if the power is out of phase. If you have dual power supplies plugged into different outlets in your house, they may be on a different phasing from your breaker panel. The can wreak havoc on your PC’s internals.

To safely wire dual power supplies in a mining rig you need to wire them such that the components are electrically isolated and that only signalling is passing between the two.

To solve for this you need to make sure components only receive power from one power supply.  For example, plug the ATX power connector and the CPU power connector to the motherboard from power supply one only.  On power supply two, make sure the VGA power connector and riser power both come form the same power supply.

Never plug the riser into power supply one, and the GPU into power supply two.  This can be an easy mistake to make if you’re not paying attention!  Try as much as possible to spread the load across both power supplies evenly.