Question Graphics error after installing SSD or How to ruin your Christmas just in time

[yepstilldoesntwork]

It was Christmas Eve when I installed my first SSD. It's a WD BLACK SN750 just arrived that I put in its M.2 slot. So, I started the pc and.....it didn't even POST, black screen (GPU fan going on thou). The mobo (asus Z270-a) signaled a VGA error and it kept BEEPing, indefinitely. I removed the SSD, and still didn't work. At this point reading some online discussions, I started thinking that it was a CPU fault (i5 7600k), having just 16 PCI lanes, whereas I had already 16 from my graphic card (Gigabyte Aorus 1060 6gb) + 4 now with the SSD. Still, being not an expert, I'm not sure if this is the real issue, and if I have to actual change this SSD to a SATA one. But the problem didn't end here. I removed the graphic card and connected the monitor directly to the mobo in order to use the integrated graphics, but, very strangely, when I started the pc, nothing changed from the previous situation. Last thing I tried was using a different PCI slot for the graphic card, and this time, well, there was no more beeping, not even one, but every other issue remained.
Anyone of you knows how to give me this special gift by explaining how to solve my problem? Many thanks in advance

 

[drivinfast247]

Put everything back the way it was before and clear CMOS.

 

[RealBeast]

Did you install the M.2 drive in M2_1 or M2_2? (and in case it matters, the M.2_2 socket shares SATA_56 ports when use M.2 PCIE mode device in X4 mode. Adjust BIOS settings to use M.2 PCIE devices in X4 mode.)
And no worries, you have plenty of PCIe lanes for a GPU and M.2.

And as already said, clear the CMOS.

 

[yepstilldoesntwork]

Thanks for answering. I put everything back and cleared the CMOS in all the possible ways, but, unfortunately, nothing changed. As for the M.2 drivers, I don't remember installing them; anyways, I don't think there is any way of installing them right now in this current situation.