Kinda new to Linux, so sorry if I'm missing something easy with this. Last Thursday I had a problem with my Linux Mint (17.1) install on my laptop in that it would boot up to the splash screen and then stop. I'm using full system encryption, so this is the point in the boot when it should have been asking me my passphrase, but it didn't. It just sat there. I've been using Mint for months without trouble until Thursday, so I was confused what may have gone wrong.

I looked all over for assistance but couldn't find anything, and ultimately ended up reloading my laptop from scratch. Been using it all weekend without trouble again. Until just now. Same issue. I can't boot past the initial splash screen and it never asks me my passphrase. Just its there.

I don't recall what, if anything, I may have done last Thursday but the only thing I just did before this similar error was rebooted, entered into the bios and changed the system time (it keeps drifting by several hours). Saved and exited, and here I sit at the splash screen. Changing time back in the system bios to what it was before I changed it did not resolve the issue... wasn't sure that it would but I tried it anyway.

So, I've been searching again and have only found the one thread here on the forum that deals with this issue (http://www.linuxquestions.org/questi...en-4175536977/) but ultimately that guy did the same thing I did last Thursday. And I really don't want to re-load again. And I really want to know what this is all about, and why it's now happened twice within 4 days.

Does anyone have any guidance on what I should be looking at? Thanks in advance.

"full system encrption" may mean different things to different people.
Post a link to the webpage you used to do the install - the more complete the page the better.

Which splash screen are you talking of ?.
Is /boot encrypted ?. Are you using LVM ?. Is LVM on crypt partitions, or is LVM the base, and crypt run on the lvs ?.

No page. During install it asks you if you want to encrypt the system and I did. So when I say the initial splash screen, I do mean the very first splash screen where it would normally ask you the encryption password and then proceeds through the rest of the OS boot.

Since this doesn't seem to be a simple topic, or easily discerned I'm just going to reload again. I need my laptop functional. Would still be nice to know what may be going on so I don't do whatever I might be doing, and have to go through this a third time. Thanks all.

That might be a worry - CMOS battery starting to fail ?. How old is the computer ?.

I don't see the point of encryption, so have never tested it. As it happens the laptop I had Win10 preview on started complaining, so I trashed it and did a Mint 17 encrypted install just for experience.
Seriously shabby experience IMHO. It encrypts the root partition, but not /boot, or the EFI partition. Hardly my idea of "fully encrypted", but that's indeed what they call it.
Grub is set to hidden with a zero timeout value, so you never get to see the boot menu.
Idiots.
If you are seeing the splash screen, grub has done it's job, and the initramfs is in control - it's the guy that prompts for the passphrase.
So, you either have a disk that is starting to fail, or the BIOS issue is having effects elsewhere. To eliminate the disk, you need to run the SMART tests. You haven't mentioned a desktop environment, but in Cinnamon, hit the "menu" bottom left, type in disks and hit "enter". Select the disk, and hit the little gear icon top right. Run the test even if it says the disk is ok.