I have a desktop PC and all of a sudden it couldn't boot. It would either hang at the Windows loading screen or once logged in immediately freeze. I repairing from a live cd but that froze as well. This led me to believe it is a hardware problem. I opened the case and checked connections and cleaned out the dust.

I have a SSD with the OS installed and an internal hard drive for storage. When I reset the bios to default settings it said it couldn't find an operating system. I went back to the bios and changed things and it booted. I am now able to log in and use the computer.

My question is 1) does it matter which molex power connector you connect to which hard drive? 2) does it matter which sata cable is connected to which drive? I'm not sure if the primary hard drive needs a certain one. Are there any other considerations when adding a second hard drive, I know the BIOS settings need to specify master/slave.


SATA not require JUMPERS this means you need to tell the motherboard's BIOS which drive to boot from.

The power cables all the same you can connect to anyone you want, but in some cheap power supply it's recommend to take the cable that no other devices attach to it.

NOTE: Some motherboard require to mange the cables by the numbers, so PORT number 1 for Master and others for slaves. other motherboards have SATAII and SATAIII ports, so read the motherboard datasheet to be sure what you are doing.

enter image description here

  • 1
    I found the problem. The BIOS detected the new drive but by default it has the SATA controller disabled (even if it detects something is connected to it!) So it had to be enabled. Out of curiosity do you know why they would design it so it would still be disabled even if it saw a device connected? – northerner Feb 20 '17 at 11:58
  • In some cases Normal boot into Windows will be disabled when SATA drive is enabled, Second it will take time to bootup your system, because there is checkup process for all ports in every boot. so why checking ports while there is nothing attached to it!! – Narzan Q. Feb 20 '17 at 12:23

The Master/Slave era disspear with IDE drives and replaced by SATA.

On your first attemp the bios did not find an OS because the order.

On any systems, usually, there are two types of order when talking about about SATA drives/ODDs. One is the order stablish by physical cables on a BIOS default setting and the other one is the BIOS boot order.

No matter which method you use to order this, but once stablish the BIOS will look for a OS on the first device (ordered by cable or bios boot order), if it does not find any OS on the first drive it will not jump to the second one, you need to reorder and make sure the OS is on the first place.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.