How many devices can hang on one MOLEX?

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How many devices can hang on one MOLEX?

Post by Anatorax » Mon Oct 11, 2010 4:56 am

Hi, guys!

I am using a molex extension cable and have many devices attached to it (each device has a "molex tail", a Y-cable, so that I can attach one more to it and so on). My question is how many devices can I power up with one cable? Is there any limitation; should I use the PSU cables rather than hang everything on one extension cable?

So far I have one HDD, one DVD-ROM, fan controller with 4 fans and few lights attached to each other via molex, connected to one cable. Should change the configuration? Can add an extra HDD? The PSU cables are fat and messy, so I would prefer to use a single molex extension cable rather than those ugly cables.


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Post by 1kbyte » Mon Oct 11, 2010 6:51 am

Stressing single connection with several devices are not a good idea. Over current could fried the main cable/molex connector

By the way, what kind of lights on your setup? is it LED or CCFL?
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Post by Anatorax » Mon Oct 11, 2010 7:38 am

Thanks for the advice!

I have two 30cm long CCFL lights.

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Post by bonestonne » Mon Oct 11, 2010 9:12 am

After a point, it is safer to start using other Molex plugs on the PSU. After 4 devices, you're starting to pull a little stronger on the capacitors that regulate that specific strand.

I think i have 4 or 5 devices splitting off one plug, and I pulled out another one to take the load off after undervolting 5 fans.
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Post by Erelyes » Mon Oct 11, 2010 3:36 pm

It depends on the wire gauge on your particular molex. The thinner the wire, the less current it can handle.

As a rule of thumb, if you can feel warmth anywhere along the cable, it's being overstressed.

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