I've experienced what you guys are talking about prime vs linx, but in my seek for stability I've found a very interesting thing. I'll leave here what I did:

2600k 1.415v:

- 21 runs linX with Ht off stable ( it's in zalbard linX club the screenshot for this ).

Went to bios enabled HT:

- Prime BSOD 0x000124 on me like 15secs after start
- LinX 4C8T with [all] run for about an hour (15/16 runs ? ) wasn't in the mood to let it end...

went to bios and bumped the vCore to 1.425, and left it runing prime for the rest of the night ( 8hours give or take )

-It was still runing today...

But when I tryed to prove me point earlyer on this topic, I got a BSOD after the 3rd run with LinX, having him runing only in 4 cores...

It's still run's a lot of time with linX in all the 8 threads...

I've tryed to bump, and reduce vCore so far from 1.4v ~ 1.43v in Bios the results are all the same, so give it a litle bit more VccIO ( 1.15v ) and it's still runing...

In the end I think with this sandy it is yet to be the perfect test, I would make the CPU pass a mix of them, then I would gladly know it's stable