POWER FAILURE: HDDs DISAPPEARED... ALL OF THEM ON PC

[n25an]

I have three hard drives on my pc
1 -- 1 tb (OS)
1 -- 2 tb (emulated games)
1 -- 5 tb (pc games)

I had a power outage just a 5 second hiccup... off then on again...

my pc crashed... I have no ups (buying one now)
first boot 5tb was uninitialized
second boot os was not found
third boot no hard drives found on pc...

at this point I was panicked...

then I went into bios and changed from legacy to uefi
and change power setting to prepower outage... (dell who knew)
then I booted... no hdd discovered
went back in and changed back to legacy... hard drives magically appeared...
rebooted

and have been fully functional ever since...

makes me wonder... how many times I had formatted hard drives when I had to just change a setting...
please let me know your thoughts...
is it a fluke or did I stumble unto something...???
as always I bow to the grey beards awesomeness...

[rthonpm]

Make sure you have the BIOS and any drive firmware up to date as well. I recall quite a few issues with drive detection on several models of Dell machines due to a timing issue. You'll also want to make sure that the POST settings in the BIOS are set to thorough instead of quick or automatic for startup if that setting exists.

Long-term, if you're still using legacy boot, you may want to look at changing to UEFI as it is more stable for boot issues and before too much longer a lot of operating systems will likely start to drop, or at least deprecate, support for it.