Octominer 8 GPU Cryptocurrency Mining Rig Build

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We’ve been wanting to build an Octominer 8 GPU Cryptocurrency Mining rig for quite some time. We were initially going to buy a new set of video cards for the project. But, after another 8 GPU rig suffered the loss of one, then another riser card, we decided to strip it of it’s GPUs and use them on this build.

Note: Ocotominer appears to have gone out of business. While we have yet to try it, there appears to be a slew of Ocotominer 8 GPU Motherboard knockoffs on the market. We will link to those motherboards but want to be clear that we have not tried one yet. If you do try one and are successful, we’d love to hear your story so it can help others!

Contents
Hardware shopping list
Prepare Windows 10
Assemble the minimum mining rig hardware
Install and configure Windows 10
Add remaining GPUs
Build Gallery

If you’re a beginner, and looking for a step-by-step build guide, you may instead want to consider our 6 GPU Mining Rig build. Although a 6 GPU rig, the hardware used in that build can run 8 GPUs.

Octominer B8PLUS: a riser-less 8 GPU motherboard

If you haven’t heard of the Octominer motherboard before, the title of this section tells you everything you need to know. If you’ve become frustrated with the lackluster quality of risers, this board is likely for you. The B8PLUS is longer than a traditional motherboard to allow for it’s 8 PCI-e slots and ample space between them.

Octominer B8PLUS Mining Motherboard

Octominer B8PLUS Mining Motherboard

The Octominer has a clever design that makes it’s price-point attractive. At approximately $199 USD you are getting a motherboard and CPU. And, you don’t need to purchase riser cards. As far as hardware cost goes, the math works out better than any 8 GPU solution requiring riser cards.

This build will include instructions for installing and configuring Windows 10. You can use any GPUs you wish, although if using AMD GPUs you will need to figure out BIOS flashing on your own.

Octominer 8 GPU mining rig hardware list

Everything you need to buy is listed below. Where possible we provided alternate items in the event something is out of stock.

Retired Motherboard (Ocotominer)

  • Octominer B8PLUS Motherboard – This link is still provided as a reference but Ocotominer appears to have gone out of business. The motherboards listed below are knockoffs that are being sold on Amazon.

Octominer 8 GPU Riserless Motherboard Knockoffs

RAM (SODIMM)

Both of the knockoff boards take DDR3 RAM (it’s not a misprint). Specifically, it is a single DDR3 SODIMM slot which supports 1066/1333/1600MHz RAM including:

Video cards

Important: We have build this rig with GTX 10xx series cards and it worked great. The cards we used were watercooled GTX 1070 Hybrids. If you are going to attempt a build with one of the knockoff boards above, you should inquire and see if there is enough room to use newer, wider RTX 20xx and RTX 30xx cards. You may have to use every other on-board slot and 4 risers to get 8 of these wider cards to work.

  • 8x Nvida GTX 1070s including any of these by EVGAMSI or ASUS  or
  • 8x Nvidia GTX 1070 Tis including any of these by EVGAMSI or ASUS  or
  • 8x Nvidia GTX 1080s including any of these by EVGAMSI or ASUS  or
  • 8x Nvidia GTX 1080 Tis including any of these by EVGAMSI or No products found.  or
  • 8x AMD RX 570 8GB including any of these by MSI or
  • 8x AMD RX 580 8GB including any of these by Gigabyte or MSI

Note: Any of the video cards above will work fine for this build. Our cards, GTX 1070 EVGA Hybrids (watercooled),, were from a different project. You don’t need to buy watercooled cards, nor do you need all 8 GPUs to start the project. To get the rig up and running you’ll need at least one GPU.

Power supply

Regardless of the power supply, using any ATX PSU with the Octominer B8PLUS requires a PSU Jumper

Important: If you use newer RTX 20xx or 30xx cards, you will likely require more PSU power. Contact us if you’re going to try this approach and let us know the video cards you’ll be using (and how many) and we can help calculate the total power need.

Note: If you purchase GPUs that require more than a single 8-pin or single 6-pin PCI-e cable you may need to purchase additional cabling. Both the EVGA P2 and T2 ship with 9x 8pin (6+2) cables and 5x 6pin cables.

Note: In our build we will be using two power supplies that we were not using. Our instructions will be for the single 1600W PSU, however.

8 GPU mining rig frame

Regardless of the mining rig frame, also pick up some zip ties to secure cables (and if using the shelving unit, hang the GPUs).

120 GB+ SSD and data cable

SSD Drive

Data Cable

8 GB or large flash drive for Windows 10 installation

Items to only buy if you have to (buy if you have to)

You’ll need these items to complete the build. Hopefully you can borrow them as opposed to buying them.

Prepare Windows 10

To install Windows 10 we’ll need a USB with a bootable install. Here’s how:

  1. Visit the Windows 10 ISO page
  2. Select the version of Windows 10 you want
  3. Using the Flash drive you bought create the bootable USB
8 GPU Octominer B8PLUS

A complete 8 GPU Octominer B8PLUS build

Assemble the minimum mining rig hardware

  1. Build the mining rig frame
  2. If using wire shelving, cut a piece of cardboard the same size as the Octominer motherboard to serve as a shield between the motherboard’s and the metal shelving
  3. Secure the B8PLUS motherboard on the mining rig frame
  4. Seat the RAM into the ram slot then gently push the RAM down until it seats. If necessary to install the RAM, unplug the wire going from the CPU fan to the motherboard.
  5. Using the purchased SSD cable and the 4-pin power cable that came with the Octominer connect the SSD drive and mount it to the mining rig frame
  6. Place the power supply on the mining rig frame. You can permanently secure it now or wait until all the cabling is complete.
  7. Plug the PSU Jumper into one end of the 24-pin cable that came with your PSU and connect the other end to the PSU. If your PSU Jumper has an on/off switch turn it to the off position.
  8. With a single PCI-e 8-pin to 2x 6+2 pin cable from the PSU, connect two 6-pin connectors on the motherboard. Plug the other end to the power supply. If the GPUs draw a great amount of power from the motherboard you may need to use more of the 3 remaining available power connections. As our video cards have water pumps and radiator fans we opted to connect all 5 of the 6-pin power connections.
  9. Open the latch on the PCI-e slot closest to the CPU. Install the first GPU in that PCI-e slot.
  10. Connect the single GPU on the motherboard to the PSU with a 8-pin to 2x 6+2 PCI-e cable.
  11. Plug in the USB WiFi adapter plug or connect the cat cable from the B8PLUS motherboard to your router.

The current state of the Octominer

At this stage you should have a mining rig frame with the Octominer motherboad mounted on it. The motherboard should have the RAM installed, the SSD data and power connected and a single GPU should be installed in the PCI-e slot closest to the CPU. At least two of the 6-pin power connections on the motherboard should be connected.

The GPU should also have it’s power connected to the PSU. The Windows 10 installation media should be in one of the USB ports on the motherboard. The monitor should be connected to the VGA port on the Octominer board and either a USB WiFi adapter should be in a USB port or a cat cable should be connected to your router.

Install and configure Windows 10

This is by far the longest step due to the number of updates that Windows needs to install. Hopefully beyond the time commitment your installation goes as smooth as ours did.

Installing Windows 10

  1. All power switches should be off. Make sure the switch on the power supply is in the off position and if your PSU jumper has a switch also turn it to the off position.
  2. Plug the Windows 10 Installation flash drive in to a USB port on the motherboard.
  3. Connect the keyboard, mouse and monitor to the Octominer motherboard.
    • You may need to use the USB Hub as more items will be connected by USB.
    • The monitor needs to be connected to the VGA input on the B8PLUS
  4. Connect the power cable to a wall outlet and turn on the power supply. If your PSU jumper has a switch, also turn it on.
  5. The Octominer B8PLUS will boot, briefly showing the Ocotminer logo on the screen.
  6. Allow the boot process to continue. The Windows 10 Installer will take over.
  7. Completely install Windows 10, including all updates.
    • There will likely be several updates and it will likely take two or more hours.
    • The miner will reboot several times during this process.
  8. When asked by the Windows installer, turn off (or reject) any non-essential functionality.
  9. Once Windows is completely installed, remove the Windows 10 installer USB Flash drive.

Configuring Windows 10 and the B8PLUS for Mining

  1. Download and install the most recent drivers for your video card.
  2. Open Device Manager
  3. In Device Manager, locate the single GPU that you installed and ensure it has been identified correctly. If not, perform a clean driver install with the drivers you downloaded in step 1.
  4. Update the following Windows 10 settings:
    • In the lower-left-hand corner, right-click on the Windows Icon and select the Systemoption
    • Click on the Notification and actions option
    • Turn off everything
    • Click on Power and sleep
    • Set When plugged in, PC goes to sleep after to Never
    • Click on the About option
    • In the far right-hand column, click the System info option
    • On the screen that presented itself, click the Advanced system settings option
    • If you want to change your computer’s name on your network, click the Computer Name tab and do so
    • Click on the Advanced tab
    • Click the Settings button in the Performance section
    • Select the Adjust for best performance radio button
    • Click on the Advanced tab
    • Click the Change button in the Virtual memory section
    • Uncheck Automatically manage paging file size
    • Select the Custom size radio button
    • Set Initial size and Maximum size to 16384 MB
    • Click Ok. Windows will alert you that changes won’t take effect until you reboot.
    • Close all open windows until you are back on the About screen
    • Click on the Home option to return to the main Settings screen
    • Click on Update and Security and make changes as you wish
    • Close any open windows
  5. To continue, Windows 10 must be correctly identifying the single GPU you installed in Device Manager.
  6. Reboot the Miner
  7. Boot into the B8PLUS’ BIOS by holding down the DEL key. If the computer boots into Windows, you’ll have to try again.
  8. In the B8PLUS BIOS make the following settings:
    • In the Northbridge Configuration the option for Primary Display Boot Devices should be set to Auto
    • Locate the Primary Display setting under graphics configuration and change it to PCI.
  9. Save the changes you made and reboot by pressing the F10 key.
  10. The miner will reboot. We now need to switch to the GPU’s video output.
    • Unplug the VGA connection that has been on the onboard graphics card
    • Connect the monitor to the HDMI port on the graphics card.
  11. The miner will boot into Windows 10 using the GPU for video output.

Add remaining GPUs

  1. Completely shut down the miner and unplug the power cord from the outlet.
  2. Seat one more GPU to the B8PLUS in the closest available PCI-e slot to the CPU
  3. Connect the power connections for the freshly added GPU
  4. Boot into Windows and open Device Manager
    • Windows may become sluggish for a few seconds to several minutes when identifying a newly added GPU.
    • When it is reconciling new hardware mouse movement can be seen on the screen, but clicking is often disabled.
  5.  If Windows 10 recognizes the freshly added GPU by a generic name you will need to update the device drivers.
    • You may need to perform a fresh install of the video driers using the package you downloaded earlier.
    • In the event updating the device drivers still hasn’t worked, you can try uninstalling one of the correctly recognized GPUs in device manager, rebooting, and rerunning the driver installer downloaded earlier.
  6. Once you the added GPU is correctly recognized, install another GPU starting at step 1 until all GPUs are installed.

Octominer B8PLUS 8 GPU build gallery

Official Octominer B8PLUS install video

Here’s the official video installation from the Octominer website. Please note that it is slightly different than our build, but we’re including it as it provide guidance along the way. The build uses an Octominer B8PLUS 4U Rack, GTX 1060 GPUs and a Linux operating system.

Troubleshooting

Our install was straightforward and we hope yours is, too! If you do get stuck along the way, Octominer visit the Octominer B8PLUS Setup page. There are some suggestions at the bottom of the page.

Download additional software and start mining!

Once all the GPUs have been recognized, you’re just about ready to start mining. Install any overclocking utilities and your chosen remote desktop solution if you use one. Don’t forget that you may need to put an HDMI Dummy Plug into the first GPU’s HDMI port for remote desktop connections to properly display the miner’s screen.

All that’s left is to download the mining software for the cryptocurrency you wish to mine, get your wallet setup and start mining!