SSD failure

[GerardV]

My laptop has a 500 GB OCZ SSD divided in 6 partitions.
Sda1 and 2 for / and /home, Kubuntu, sda 3 and 4 for / and /home SolydK, sda 5 Swap and sda6, for whatever distro i want to check out.
Yesterday i installed Mageia on a external ssd and placed the bootloader on that drive. (Don't bother with that one).
When i tried to boot into Kubuntu, i ran into all sorts of problems, mainly to do with wrong UUIDs.
Eventually i got it going but found myself booting into a pristine desktop, thinking all the ~/.kde/config and ~/.config files have been changed/deleted.
When i started Dolphin i noticed that none of my partitions showed up in the sidebar except sda1, / for Kubuntu and sda3, / for SolydK.
When i fired up Kpartition manager, sda showed as having 136 Gb only, and unallocated. .
Clearly it was allocated to something.
I restarted the laptop with a Gparted cd to see what's going on.
Gparted reported the same and helpfully informing me that i had an invalid partition table.
So i installed a new partition table hoping that would fix it. It didn't.
So where did the other 364 Gb go?
I did have a monthly cron job for trimming the SSD and had plenty of free space left.
I re-installed SolydK as it was the only DVD i had lying around and everything works fine except i am down 364 Gb.
Anyone got any idea ?

PS The 136 Gb size does not match any of the old partitions in size

[InsideJob]

gparted is the authority so there's no point questioning it. What I'd do is execute (as in kill) the partition table with:
sudo dd count=512 if=/dev/zero of=/dev/sdX (where X is the SSD as seen from a LiveCD or USB stick)
then use gparted to make a new one. Of course, all data will be lost from all partitions, so backup anything you want to keep.

[SteveRiley]

What's the output of:

sudo fdisk -l /dev/sda

sudo gdisk -l /dev/sda

[SteveRiley]

Didn't notice that. Sigh....

[InsideJob]

It's still a good question. I have this problem all the time when playing with BSD. Zero the first sector and the drive becomes usable again.

[GerardV]

Thanks for replying guys, a bit surprised myself

I have since replaced that SSD with a Intel 240 GB SSD, just don't trust the old one anymore.
It is still going though, minus the 360 odd GB.

[InsideJob]

Check the SMART data. If it doesn't report any errors it's almost certainly just a bad partition table. Those are the only two possibilities, bad partition table or bad media.

I got a virus once (Winblows, Jerusalem-B variant) that encrypted the file allocation table... that was a real pain.