MSI 815 PRO Manual page 7

2.1-3 Overclocking Jumper: SW1
Overclocking is operating a CPU/Processor beyond its specified
frequency. SW1 jumper is used for overclocking.
SW1
1 4
5
2
6
3
1
4
2 5
6
3
6
3
5 2
1
4
1 4
5
2
6
3
Note: If you used this jumper for overclocking, you also need to
modify the CPU Bus ratio through BIOS.
Function
Auto detect/Default
Set from 133MHz to 160MHz through BIOS (DRAM: PC133)
Set from 133MHz to 167MHz through BIOS (DRAM: PC100)
Set from 100MHz to 150MHz through BIOS
Set from 66MHz to 100MHz through BIOS
2-3
SW1