Hello all. Just this week I got my 270 Classified K and on my quest for 5.2ghz (7700k) I've been having a slew of BSODs and sadly I have encountered a critical issue that I have yet to find a rhythm or reason to.  About 1/6th of the time my computer power cycles (even regular without BSOD), my Intel 750, which is also my boot drive, just ceases to register altogether. For clarification, it will not register it as a device or even that it is populating the PCIE6 slot. For whatever reason however if I move it to PCIE4 it will still not register the slot as being populated, but it will move my video card down to x8 almost as if it does register it. I have yet to find any solution to this and my method of solving it when it occurs it to just turn off computer and turn on computer around 20 times and hope that I get lucky and it pops up on one of them. 
 
As additional information the Intel 750 has some lights on it. Green for good, orange for bad. When it disappears I have zero lights almost as if the board isn't giving it any power. If I pop it in my roommate's computer, the drive acts normal.
 
I've found this thread using google and have applied the recommendations within, but to no discernible result. 
 
( I guess I cannot post links as I have too low post count, but if you google: "intel 750 not showing up evga" it is the first link with the x99 guy).
 
I'm at quite the loss as to what to do here and would greatly appreciate any help.My bios is also on the latest version (1.03).  
 
Edit: some pictures
 
Here is the the drive being absent

 
Here is the drive being present. Also while present if I click the "NVMe Information page" it populates as "No NVME Device Found."

Sajin
Going off your pictures... looks like the overclock is the cause of the problem.

The second set of pictures is it just after I got the drive to appear again after trying the bios switches and then clear cmos. Unfortunately those did not result in it popping up immediately. Still had to do a few reboots. 

Sajin
All three bios versions (1.01, 1.02 & 1.03) experience the same issue?

I haven't tried 1.02. I went directly from factory to 1.03 (since it mentioned something about PCIE devices in patch notes). I'll try 1.02 if that is your recommendation. But yes, it was present on factory bios (1.01?) and 1.03.

I tried 1.01 and 1.02. The problem is present in both of those versions as well. 
 
When the drive is not registering I have also unplugged my other drives and disabled Marvell and Sata-e along with M2s but it does not appear to make a difference.
 
I've also noticed Intel released a 750 update 2 weeks ago. I will update it tomorrow once I get my USB from work and will post again whether solves the issue. 

So I updated the 750 to the latest firmware and it didn't fix anything. However I have stumbled across a what I believe to be a fix. When I said I had attempted the bios switches before I was only partially correct. I thought there was only two stages to the switch not three (in my defense it was 3am). It appears to work every time on the third level of the switch, although the post screen appears to be different on it. Also I've noticed one large difference on it versus BIO #1. 
 

 
In Bios #1 this page was blank as shown in one of my OP pictures. I don't know the significance of it, but it makes me feel better and cleared me of doubt that my drive was going bad. Hopefully some EVGA engineer can use some of the information I've presented and work it into the next update. Would be horrible if this happened attempting first post. Would completely think a part is dead and rip apart computer and begin massive trouble shooting. As additional information I've never gotten the drive to appear on Bios #2. It just refuses no matter how many times I power cycle. 
 
Also as a question, I thought the BIOS switch would just switch between default configurations of the bios, kinda like a profile I could set up with a physical switch. But it would appear that there are larger differences than that? Bios #2 also has a different post screen than Bios #1 and #3. If anyone could inform me of the differences I would appreciate it. The manual doesn't seem to mention anything about it I can find. 

Look at the bios version for each switch posistion. Since 3 is working then that is the version I would use. As noted the switch is tied to completely different bios chip.

The problem is still occurring. Although I would say much less often than Bios 1 (maybe since its random and I cannot produce the error). I'm at a loss for what to do. I'm skeptical that it is a hardware problem with the board yet I don't know enough and am not a authority on such matters to make a decisive claim one way or the other. However each time I pop in my roommate's computer the drive reads and I pop it back in mine and it acts like it doesn't get power irrespective of PCIE slot. If anyone has any further suggestions or methods of troubleshooting. I will do whatever you suggest/ask. 

quadlatte
what are your boot setting at? secure boot on? CSM? 

Hello. Sorry for not noticing reply to the thread. I don't recall my exact boot settings, however I have the recommended for the Intel 750. I've found the underlying issue to the problem which is the 750 fails to initialize when the ram is set to 3000mhz or faster. The problem is also documented in this thread which is how I found it. https://forums.evga.com/z170-classified-intel-750-not-recognized-with-memory-set-to-3000Mhz-m2392702.aspx
 
I've notified Evga tech support and they've replied that they are working on a fix to the problem. In the meanwhile I will also just have to leave my ram at 2900.  
 
I was mistaken before and when the drive is not being recognized, clearing the cmos is the only thing that will appear to fix it besides getting lucky rebooting a dozen(s) times. I was probably silly and switched to a different bios that I had already overclocked the ram on after doing it. 

glad you got it figured out. ever since intel moved the memory controller and pcie lane control on to the cpu i have seen some strange things happen.