Raid 0 boot Issue Ubuntu 16.04

[maybememe]

Hi guys,

I have an Acer Aspire S7 ultrabook with two 128gb SSD's and bios controlled raid mode does not seem disable-able.

So I figured out how to install Ubuntu Via raid 0 by following this guide on page 18.

http://dl.fullcirclemagazine.org/issue104_en.pdf

It was working OK, then for a moment would only boot to a blank underscore blinking.
I shut it off and on and it booted OK after that.

Now weeks or so later it's only booting to the blank underscore character blinking infinetly.
Nothing I do now will help.

I tried holding down shift at boot, yet no advanced grub options come up. I have verified all of the raid partitions are still intact via a live usb.
I also generated the following boot info and uploaded to paste bin via boot-repair

http://paste2.org/YPAKvCKI

Can anyone help?

[maybememe]

Update: The system boots OK when I load first from what appears to be the Live USB thumb drive I used to first install the raid setup from.
It loads the two SSD's configured in Raid as one striped partition, not the actual Live environment on the USB.

[oldfred]

Do not know RAID, but a couple of other S7's. Yours now seems to be a BIOS install, not UEFI.

Acer S7 14.04 & Windows 8.1 RAID
http://askubuntu.com/questions/590644/install-ubuntu-14-04-2-lts-alongside-windows-8-1-dual-boot-on-raid-acer-s7-quest
acer aspire s7 Dual SSD RAID - [SOLVED] Installed Ubuntu on Pre- UEFI Win
http://ubuntuforums.org/showthread.php?t=2240043
Acer Aspire S7 can't install ubuntu - UltraBook erased RAID meta-data
http://ubuntuforums.org/showthread.php?t=2121187

[maybememe]

Thanks for your reply, and to clarify, I have already installed Ubuntu 16.04 via Raid 0 by flipping legacy mode on and EFI off.

The install initially worked fine. Then intermittently 2-3x would only boot to a black background and blinking underscore, I'd power cycle and it would be okay after several tries.

Then I noticed I could boot no problem via sdc1 which is an adata 32gb flash drive I built a USB windows 10 install onto with Linux Live USB creator. It contains GRUB and so when I hit fn+f12 to change the boot to occur from the USB drive instead of HD0 / sda1 it works.

I have been attempting to utilize boot-repair to fix the situation, yet it hasn't worked no matter what advanced config I try.

I have generated a boot config report to pastebin here for analysis:
http://paste2.org/ehffHNC8

It has noted that...

sda1: __________________________________________________ ________________________

File system: ext4
Boot sector type: Grub2 (v1.99-2.00)
Boot sector info: Grub2 (v1.99-2.00) is installed in the boot sector of
sda1 and looks at sector 281538 of the same hard drive
for core.img, but core.img can not be found at this
location.
Operating System:
Boot files: /grub/grub.cfg


I suspect the error is in core.img not being found, yet am not sure how to fix it?

[maybememe]

So I ran the grub reinstall command manually on sda, that reinstalled grub but still found no kernels for loading. So I reran boot-repair and with grub on sda now it knew what to do this time it appears. I can now boot to Ubuntu.