What rail powers what?

[EquaLiZr]

I know the 12v powers fans and such but aside from that what does the 5v line power and the 3.3v line power.

Does the 12v power the cpu nowadays?

hopefully this isnt a dumb question

 

[[Spectre]]

For the most part in the consumer realm 5v is logic on drives etc. 3.3v is RAM.

CPU's have indeed moved to the 12v rail.

 

[madmat]

12V on PCI-e graphics cards, 3.3V on PCI devices, 12V on drive motors, 5V on USB, 12V on Firewire and I'm sure there are others I'm missing but you get the idea.

 

[EquaLiZr]

I was just wondering cause speedfan says my 3.3v is only 3.16 but my bios says 3.35

My other voltages read 12.16v and 5.3v

 

[Kasparz]

For the most part in the consumer realm 5v is logic on drives etc. 3.3v is RAM.

CPU's have indeed moved to the 12v rail.

Some motherboards, except SD-RAM and older ones use 5v for dimm, like these boards for BH5 and some DDRII boards who can feed more than 3.3vdimm, but thats only few exceptions.

 

[madmat]

Some motherboards, except SD-RAM and older ones use 5v for dimm, like these boards for BH5 and some DDRII boards who can feed more than 3.3vdimm, but thats only few exceptions.

All the boards I've seen that do feed the ram from the 5V use a jumper to set it to that rail otherwise it's off the 3.3V rail.

 

[[Spectre]]

Some motherboards, except SD-RAM and older ones use 5v for dimm, like these boards for BH5 and some DDRII boards who can feed more than 3.3vdimm, but thats only few exceptions.

Which is why I said "for the most part". Enermax and certain motherboard provide auxillary power to the RAM via 12v.....but if I went and listed all the exceptions......well....hence the qualifer