You can dump the segment descriptor for a segment register by using the dg command:
Rich (BB code):
0: kd> dg gs
P Si Gr Pr Lo
Sel Base Limit Type l ze an es ng Flags
---- ----------------- ----------------- ---------- - -- -- -- -- --------
0000 00000000`00000000 00000000`00000000 <Reserved> 0 Nb By Np Nl 00000000
Since the present flag is cleared, then the processor will raise an exception when we attempt to access it. From the Intel documentation it states the following:
Rich (BB code):
0: kd> u nt!KiPageFault+0x3c
nt!KiPageFault+0x3c:
fffff805`3a00363c 65f604257802000001 test byte ptr gs:[278h],1
fffff805`3a003645 7508 jne nt!KiPageFault+0x4f (fffff805`3a00364f)
fffff805`3a003647 0faee8 lfence
fffff805`3a00364a e96c020000 jmp nt!KiPageFault+0x2bb (fffff805`3a0038bb)
fffff805`3a00364f 650fb604257a020000 movzx eax,byte ptr gs:[27Ah]
fffff805`3a003658 b948000000 mov ecx,48h
fffff805`3a00365d 33d2 xor edx,edx
fffff805`3a00365f 0f30 wrmsr
Have you ran any SSD diagnostics tests? This certainly appears to more of a hardware issue rather than software in my opinion.