BIOS boot issue and has UEFI boot option one time, next time it doesnt

Asus P8Z77 V Deluxe mobo.
Seasonic 1050W modular PSU
i7 2700k
Noctua NH D14 air cooler
Corsair Vengeance RAM 1600 (mobo - native is 1333mhz)

Sometimes, when I access my BIOS, on the first page I see, it will show UEFI boot disk in the boot order at the bottom of the screen.
When I access my BIOS at other times, it does not show the UEFI boot disk. (large stripe on disk icon that says UEFI).
There are times when I boot my computer, I see a black ASUS splash screen before booting into windows.
Other times, I see a Red/Black splash screen with another company's name.
Is this normal?

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The automatic boot order in BIOS, it lists 2 devices.
my mechanical harddrive (disk 0) as option 1. Then my dvd drive as option 2.
The problem is my boot drive (with OS) is on an SSD (disk 1).
I tried to change it, but the boot order only shows DVD and mechanical HDD options.
I had to use the boot override option, which lists my SSD.

I just did a fresh install of win7, then upgraded to Win10. I only had the SSD connected.
I did not remove the win7 OS from my mechanical drive until I was sure Win10 would upgrade properly on my SSD. After the upgrade was working, I connected both HDDs and booted up I got some type of boot error. No boot sector found please enter a disk or reboot - something like that.
When I rebooted with the spinner disconnected, win10 started normally, afterwhich I hot connected the spinner disk and then formatted it to use as my data drive.

Why does my boot order change like that?

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When I originally built this computer, it used to boot every time with the Red/Black splash screen.
I had the BIOS updated by a computer shop and then it started to reboot with the black ASUS splash screen.
Does that make any difference?

My 2nd PCIe slot doesn't seem to be working or be recognized, so I pressed the reset button on the motherboard, hoping that would clear the problem.

I wonder if my motherboard is going bad?
Or I screwed up the drivers?
Since getting my computer back from the computer shop, all my harddrives show up as SCSI devices in windows, even though they are SATA and connected to the SATA6 ports.
I noticed on this fresh install, that my harddrives didn't show up in my system tray, in windows.
When I installed the updated chipset drivers, my HDDs started showing up in my system tray as SCSI devices.

Afew weeks ago, I was constantly getting "USB overload" warnings and losing connection to my keyboard/mouse...
That stopped after I stopped using a particular device (Track IR5).

After years of no issues running crossfire, now, I can't get both of my video cards to be recognized, nor activate crossfire.
Tried each card in slot 1. Both cards work.
Tried 1 card in slot 2 only - get black screen.
triple fans on graphics cards are spinning, so looks like it's getting power.

Sometimes my case fans seem to be spinning too slow. I get errors on boot up and have to set that particular fan to "ignore". Usually it's the case fans I have problems with, but now it's cpu noctua fans. 1 fan is not recognized in bios, but both cpu fans are spinning.

Motherboard going bad?

This all stems from having both drives connected at the same time when you originally set this up and has caused the MBR location for both drives to be stored on one drive, your HDD (spinner). Which explains your very first boot error message (No boot sector found please enter a disk or reboot - something like that).

I would start from scratch; remove the SSD first and leave the HDD (spinner) and do a clean install on that with your original OS. Then upgrade to 10. Once done remove HDD and attach SSD and do a clean install of of original OS and then upgrade to 10 on that. This way the MBR is stored on the correct drive for each OS install and this should correct your BIOS flash screen problem.

7of9 said:

When I rebooted with the spinner disconnected, win10 started normally, afterwhich I hot connected the spinner disk and then formatted it to use as my data drive.

Everything you have stated would indicate you have boot information remaining on your mechanical hard drive. From what I understand, a standard format does not clean the boot sector. I think you need to really wipe you mechanical HD clean to eliminate your boot issue and then see if the other conditions still exist. Unfortunately, I have never been in your exact position so I can't recommend a specific procedure to remove that old boot information so here's hoping someone will followup with a specific "how to" (if they agree with my analysis).

aardvark

aardvark said:

Everything you have stated would indicate you have boot information remaining on your mechanical hard drive. From what I understand, a standard format does not clean the boot sector. I think you need to really wipe you mechanical HD clean to eliminate your boot issue and then see if the other conditions still exist. Unfortunately, I have never been in your exact position so I can't recommend a specific procedure to remove that old boot information so here's hoping someone will followup with a specific "how to" (if they agree with my analysis).
aardvark

I used diskpart to remove the partitions on the spinner drive. I thought that got rid of any Master boot files and/or partitions?
At least that's how I understood the directions.

Then, I used windows to format the full volume of the data drive.

Hi 7of9,

After navigating diskpart to select the proper drive, did you use the "clean" command?