PATA to SATA power Adapter Question ... 3.3 volts missing???

[DaveLembke]

Hello, I had to replace a Compaq 340Watt power supply that fried with a 450Watt and there was no SATA power connections available. I did however have a PATA to SATA power adapter, and put that in and it works, however I am questioning why it is able to work without the 3.3 volt feed that the prior power supply had which was an orange wire.

Is there a disadvantage to running with just 5 and 12 volts without the 3.3 volt feed to the drive?

I am guessing that the 3.3 volt feed has an importance otherwise it would not have been there... so running without it has me confused?

Thanks,

Dave

[DaveLembke]

http://en.wikipedia.org/wiki/Serial_ATA

Actually finally found the answer to my questions... Figured I would share it in case anyone else is interested who may not have known about this.

Most SATA drives dont use the 3.3 volts.

As copied and pasted below from the wiki link above:

Adaptors are available to convert a 4-pin Molex connector to SATA power connector. However, because the 4-pin Molex connectors do not provide 3.3 V power, these adapters provide only 5 V and 12 V power and leave the 3.3 V lines disconnected. This precludes the use of such adapters with drives that require 3.3 V power. Understanding this, drive manufacturers have largely left the 3.3 V power lines unused. However, without 3.3 V power, the SATA device may not be able to implement hotplugging as mentioned in the previous paragraph.

Dave