I'm looking to add three or four more drives to my system. However, I only have two sata power connectors left. There's spare molex connectors on the current module cables being used (modular power supply) as well as on the modules not in use. I've seen molex to sata adapters, but I have a couple questions..
First, is there any harm in using a molex to sata adapter?
What the guy was saying no to was plugging in both the SATA Power connection and the Molex power into a SATA drive at the same time. Early drives had both power connections. New drives I believe only have the SATA Power connection.
I have used the adapters with no problems.
Yes you can use both molex and SATA Power connections on one power cable at the same time. I do this myself.
Turns out molex to sata power converters are only safe because most hard drives only use 5v & 12v voltages. If your using a low voltage SATA device (maybe future SSD drives?), you want to pay attention. Here's the wiki ref: http://en.wikipedia.org/wiki/Serial_ATA#Power_supply.