Third monitor does not turn on.

Hello
, I have 3 monitors, and when I try to connect them to one video card, then two of them turn on and one remains black, even in the screen settings, and when I try to turn on the third through the screen settings, it says that "It was not possible to save the screen settings", about the resolution screen and colors are all the same for all monitors.

Previously, about a month ago, all three monitors worked fine, but at one point I had to reinstall Windows. was Windows 7 Professional x64, installed the same version and after that started to include only two monitors, instead of three.
What I didn’t try to do, I reinstalled all versions of Windows from XP to a dozen, Linux, I also tried different versions of drivers.
still didn't help.

For your information:
This video card has three monitors connected at the same time.
And it's not about the cables I checked on another computer.
And also when all 3 monitors are connected and only two are working, you can disable 1 of the working and enable 1 disable.
The cables from the monitors are 2 HDMI, of which 1 is included in HDMI, and the other through a regular DVI adapter, 1 Display Port.
All three monitors are absolutely identical.
When a third monitor is connected, it is detected in the system, but it is shown as a black screen and cannot be turned on.

I just don't understand what the problem is, before everything worked well, absolutely nothing has changed, except for Windows.

If anyone knows anything or has any suggestions, please tell me what the problem might be.
And if you need some more information, write and I will answer.

Processor: Indel (R) Core (TM) i7-4770 CPU @ 3.40GHz
Motherboard: Asus Maximus VII Formula
Video card: AMD Radeon R9 270 Gaming (DisplayPort, DVI (2 pcs), HDMI)
RAM: 16 GB