H150M Pro4 Motherboard

wongwc wrote: Hi I'm using H150M Pro4 motherboard with following devices: 1) Pentium Celeron G3920 2) 4Gb Ram 3) 120Gb SSD 4) PSU Cooler Master V850W 5) GTX 1060 (6Gb) GPU cards - 3 units When I plug in the 4th GTX 1060 (6Gb) GPU card, i found my PC can't boot. The bios setting of motherboard as follow: 1) Primary Graphic Adpater - Onboard 2)PCIE Link Speed - Gen1 3) IGPU Multi-Monitor - Enabled Please assist me to solve the problem or pm me if you need any further information. Thanks in advance

You have the standard problem with a PC configured for mining with multiple video cards.

Windows or whatever OS you are using allocates some of the DRAM memory for use by the system. Each video card uses some of that memory for its basic usage. Three cards are using all of that memory, no more is available. Adding the fourth card fails because there is no more or not enough of that memory to give to that card.

Some ASRock mother boards have an option in the UEFI/BIOS, Chipset Configuration screen, called Top Of Lower Usable Dram (TOLUD). Setting this option to Dynamic allows the amount of the system allocated memory to be increased as needed.

But as I said not all ASRock boards have this option. Your board's manual does not include it, but it might be added in a UEFI/BIOS update. I have no idea if your board's UEFI has this option.

Since you have only 4GB of memory in the board, that limits the size of the memory allocated to the system. Adding more memory to the PC might cause the amount of memory allocated for system use to be larger, but I cannot predict if that will happen or not.

One thing you can try to fix this is change the amount of memory allocated to the Intel iGPU. That option is in the Chipset Configuration screen, the Share Memory option. It is set to Auto by default. Try setting it to one of the smaller values. Again, I cannot predict if that will work or not.

If you don't have the TOLUD option in your UEFI, you would need a custom UEFI/BIOS that adds that option. But with only 4GB of memory now, it might not help you with the fourth card.

Using four video cards is also putting a high load on the power draw from the PCIe slots. Some boards have an extra power connector to supply more power to the PCIe slots, but your board does not have that feature. Some people with your problem will get the PC to boot after adding another video card, but the card will not be recognized in Windows. In your case where the PC won't boot usually indicates an excessive power draw from the PCIe slots, which cannot be fixed without the extra power connector on the board.

Boards meant to be used for mining will have the TOLUD option and the extra power connector for the PCIe slots. In your situation, you may have one or both of these problems.

Ok i found the problem.