PC Freezes

Hi

I have suddenly been suffering from PC freezes, where my system does not respond and I am forced to reboot

I am running Windows 7 Ultimate.

I have copied the following from the error message ;

Problem signature:
Problem Event Name: BlueScreen
OS Version: 6.1.7601.2.1.0.256.1
Locale ID: 2057

Additional information about the problem:
BCCode: 124
BCP1: 00000000
BCP2: 8638E024
BCP3: 00000000
BCP4: 00000000
OS Version: 6_1_7601
Service Pack: 1_0
Product: 256_1

Files that help describe the problem:
D:\Windows\Minidump\013114-24218-01.dmp
D:\Users\Andysan\AppData\Local\Temp\WER-53343-0.sysdata.xml

Read our privacy statement online:
Windows 7 Privacy Statement - Microsoft Windows

If the online privacy statement is not available, please read our privacy statement offline:
D:\Windows\system32\en-US\erofflps.txt

I have not upgraded any hardware of late

Does anyone know what this problem is and furthermore how to resolve?

much appreciated