BSOD while bitcoin mining for ~ 30 mins

Hey guys.

I have set up a bit coin mining rig.
Fresh windows 7 64 bit home premium. 2x6950 and 6970 on a 990fx UD7,
Using a 555BE unlocked to quad.

After setting the mining going it runs fine but randomly crashes.
Graphic card temps are bout 70 degrees and they are stock clocked atm.

Also note for some reason its been using the cpu about 75% even though it should be like 2%

Here is the info

Problem signature:
Problem Event Name: BlueScreen
OS Version: 6.1.7601.2.1.0.768.3
Locale ID: 3081
Additional information about the problem:
BCCode: 1e
BCP1: FFFFFFFFC000001D
BCP2: FFFFF80002C94C00
BCP3: 0000000000000000
BCP4: FFFFFFFFFFFFFF00
OS Version: 6_1_7601
Service Pack: 1_0
Product: 768_1
Files that help describe the problem:
C:\Windows\Minidump\072411-20170-01.dmp
C:\Users\user\AppData\Local\Temp\WER-27658-0.sysdata.xml

Thanks

Another one
Problem signature:
Problem Event Name: BlueScreen
OS Version: 6.1.7601.2.1.0.768.3
Locale ID: 3081
Additional information about the problem:
BCCode: 1e
BCP1: FFFFFFFFC0000005
BCP2: FFFFF80002CD9DA7
BCP3: 0000000000000001
BCP4: 000000000002C0D1
OS Version: 6_1_7601
Service Pack: 1_0
Product: 768_1
Files that help describe the problem:
C:\Windows\Minidump\072411-20420-01.dmp
C:\Users\user\AppData\Local\Temp\WER-27830-0.sysdata.xml

Problem signature:
Problem Event Name: BlueScreen
OS Version: 6.1.7601.2.1.0.768.3
Locale ID: 3081
Additional information about the problem:
BCCode: d1
BCP1: FFFFF87FC3F4CF34
BCP2: 0000000000000002
BCP3: 0000000000000008
BCP4: FFFFF87FC3F4CF34
OS Version: 6_1_7601
Service Pack: 1_0
Product: 768_1
Files that help describe the problem:
C:\Windows\Minidump\072411-21434-01.dmp
C:\Users\Adam\AppData\Local\Temp\WER-28906-0.sysdata.xml