What do the ratios mean?

[CaptainBill]

I'm fairly new to overclocking and in posts, I often see mem ratios of 1:1 or ratios of some sort at 4:5...what do these mean and how do you set them? Sorry for such a noob question, but I appreciate any help! Thanks

 

[Duvie]

It means the ratio of clock speed of the cpu/memory

ie

p4 1.8a = 18 x100fsb at stock 1800mhz

1:1 ratio = cpu fsb 100mhz (400mhz quad-pumped) memory 100mhz (200mhz ddr or pc1600)

3:4 ratio = cpu fsb 100mhz (400mhz quad-pumped) and memory is133mhz (266mhz ddr or pc2100)

4:5 ratio = cpu fsb 100mhz (400mhz quad-pumped) and memory is 125mhz (250mhz ddr)

3:5 ratio = cpu fsb 100mhz (400mhz quad-pumped) and memory is 166mhz (333mhz ddr or pc2700)


Ifthe mobo you buy supports it then it should be in the same menu of the bios that sets the fsb or voltages for the cpu...