how can one determine how many drives can be plugged into one cable?

[theDeviL]

i'd like to get as least cables as possible and i have 4 hard drives that i was thinking of chaining together onto one cable on the psu but I don't wanna draw too much.

 

[engiNURD]

Math... a cable has a certain rating... a drive draws a certain amount of power... but I'm no electrician. 4 drives off of one strand of molex cables should be fine, though. I've been doing that for years, haha.

 

[MrWizard6600]

Math... a cable has a certain rating... a drive draws a certain amount of power... but I'm no electrician. 4 drives off of one strand of molex cables should be fine, though. I've been doing that for years, haha.

yeah, what your really worried about here is transient load balancing, something that only H and Jonnyguru seem to pay any attention to. A Hard drive is really just a small inductive load. Once you've established your magnetic field it doesnt take much to maintain it.

Any power supply worth its salt can run 4 hard drives off a single rail without breaking a sweat.

 

[theDeviL]

thanks for the info guys much apreciated, now I take 5 is pushing you luck?

 

[Nacho]

I run 15 drives off a single strand, so 5 shouldn't be a problem.

 

[evilsofa]

The most inefficient hard drives (back a couple of generations) used about 30W during spinup and 15W afterwards; modern hard drives cut those wattages in half. I'm not sure where SSDs are at for power usage now.