Blue Screen BCCode 50

Hello. I have a lot of blue screen problem.Here are the 3 of them.Please help.

1-

Problem Signature:
Problem Event Name: BlueScreen
OS Version:6.1.7601.2.1.0.256.1
Local ID:1055

Additional information about the problem:
BCCode: 50
BCP1: FFFFF800047B7D60
BCP2: 0000000000000000
BCP3: FFFFF8000229F7D6
BCP4: 0000000000000002
OS Version: 6_1_7601
Service Pack: 1_0
Product: 256_1


2-

Problem Signature:
Problem Event Name: BlueScreen
OS Version:6.1.7601.2.1.0.256.1
Local ID:1055

Additional information about the problem:
BCCode: 7f
BCP1: 0000000000000008
BCP2: 0000000080050031
BCP3: 00000000000006F8
BCP4: FFFFF8000229F550
OS Version: 6_1_7601
Service Pack: 1_0
Product: 256_1


3-


Problem Signature:
Problem Event Name: BlueScreen
OS Version:6.1.7601.2.1.0.256.1
Local ID:1055


Additional information about the problem:
BCCode: 3b
BCP1: 00000000C0000005
BCP2: FFFFF800022717C8
BCP3: FFFFF880094B7B00
BCP4: 000000000000000
OS Version: 6_1_7601
Service Pack: 1_0
Product: 256_1



Please help. I have blue screen problem every 20 minutes.And they are all usually different.Thaks

Here

Hello again. Another blue screen error happened a moments ago.

Problem Signature:
Problem Event Name: BlueScreen
OS Version:6.1.7601.2.1.0.256.1
Local ID:1055

Additional information about the problem:
BCCode: 50
BCP1: FFFFF88053D038E0
BCP2: 0000000000000000
BCP3: FFFFF800022D77E2
BCP4: 0000000000000005
OS Version: 6_1_7601
Service Pack: 1_0
Product: 256_1