SATA data cables keep melting

Thanks for responding. I took the motherboard out of the case again. Connected 24- and 8-pin power cables, power button, memory, and SSD. With SSD power cable and data cable connected, cpu fan spins about a second and shuts off. Push power button again and get nothing. Unplug data cable & plug it back in and push case power button and cpu fan again spins for a second and turns off. Disconnecting data cable (but leaving SATA power cable plugged in) and then pushing power button causes cpu fan to come on and stay on.

The super frustrating part is that the symptoms are inconsistent. When I started, the cpu was shutting itself off in the case. Took everything out, tried some stuff and got Intel to replace the cpu fan (which meant replacing the whole cpu). With the new cpu (& its stock cooler) everything worked on the test bench (SSD & HDD - didn't test DVD on the bench). Put everything back in the case, testing at each step and everything worked till I connected the DVD drive. Then the SATA data cable melted.

I wrote a test plan and started testing various combinations. At first everything worked with 2 devices (SSD & HDD) connected. But then I tried a different power cable and for each of the 3 devices (one at a time), the cpu fan kept running at power on as long as the data cable was not connected. In each case when I connected the data cable the cpu would power down after about a second.

I should have quit there, but I tried TWO devices with that power cable and that's when I got smoke again. Now I get the same thing when I do the test with the first power cable. I think that's due to something else, not the power cables themselves, which are pretty simple things. Just to check, I opened the SATA connectors and checked the wiring and did not see any problem. Also did continuity tests with no problem.

Seems like it must be the motherboard. What do you think? Any other suggestions?

Scout_03: Thanks for responding. I get the same result with 2 DVD players and the SSD.

I followed ahnilated's suggestion and took the mobo out of the case (again). It puzzles me that I get different symptoms in the case than I do out of the case. Out of the case, the cpu fan stops spinning within a second of turning the system on. I'm assuming that means the cpu is shutting itself off. IN the case, the cpu stays on (fan keeps spinning), but the SATA data cable gets so hot I see the wires in it glowing bright red as the insulation disappears in a cloud of smoke (at the connector that plugs into the SSD or DVD player) before I can get the power off (and I keep my finger on the PSU power switch when I push the case power button).

I've tried several different power cables and data cables and all 6 SATA connectors on the motherboard and all 3 SATA outlets on the modular PSU. I've tried 3 different devices (2 DVDs & SSD).

Thanks! I got an RMA for the motherboard and in preparing to send it back discovered several bent pins in the cpu socket, so I had to buy another one. The problem persists with the new mobo. I forgot I had this response from you and opened up a new thread under Power Supplies. I measured some voltages (and they don't make sense to me), but I did not take the psu out of the case. I did take the motherboard out, which seems like it would accomplish the same thing, but "seems like" is not the same as "does", so I will repeat the measurements with both psu & motherboard out of the case. I apologize for forgetting your valuable advice. Here's the other post (new motherboard) (Is there a way to insert tables here? The Forum software strips out my tabs and extra spaces, making the table harder to read.):

I’ve had a couple of other threads here about the SATA data cable burning up (well, melting in a cloud of smoke in the half second it takes me to shut off the power supply) on a new build. I still haven’t solved the problem. Intel replaced the cpu and I replaced the motherboard after damaging cpu socket pins by taking things apart & putting them back together. An ASRock technician thinks a bad power supply is the culprit. I removed the motherboard and put it on a towel next to (not touching) the computer (still mounted to a removable metal tray). I took a SATA power cable apart so I could measure the voltages between the colored wires and the black wires and between all wires and the case and the motherboard. The results are shown below (with apologies for the formatting - I had a hard time with it). They were not what I expected and I don’t understand what they are telling me. Can anyone enlighten me?

The meter reads a 9 volt battery at 9v and a AA battery at 1.48 to 1.5v, so it seems to be accurate.

Voltage from this wire on the SATA power cable
Orange Black #1 Red Black #2 Yellow
(+3.3v) (Ground) (+5v) (Ground) (+12v)
to: ----------- ------------- --------- ------------- ---------
Case 0v +5v 0v +5v +10v
Mobo Tray 0v +5v 0v +5v +10v
Black Wire #1 -5v NA -5v 0 +6.5v
Black Wire #2 -5v 0 -5v NA +6.5v
Mobo Tray with 8-pin cpu plug disconnected* +6.5v
* cpu fan kept coming on for ~ a second, then stopping and restarting, so I turned the psu off. Only saw the voltage to the yellow wire briefly before that, but it looked like it was about where it was before.

After replacing my 15 year old multimeter, I determined that I'm getting +5v, +3.3v, +12v to all the appropriate wires and a little less than -11v to the blue wire, so those all seem OK. But I get the same voltages whether I use a black wire or the psu case as ground. Is that supposed to be that way?