Troubleshooting A Faulty SATA Port – How To Test and Fix It
The symptoms can also be very similar to those caused by other hardware and software issues. Unless you pin down the cause of the problem, it’s difficult to be sure if any ‘repair’ has worked – or if the problem will return in a few days…
A perfect example of this is an issue I saw recently in my computer repair business – it turned out to be caused by a faulty SATA port on the motherboard.
I’ll explain below how I troubleshooted and fixed it – it reinforces the need to have a logical approach and not to become so blinded by the ‘most common’ causes that you fail to consider rarer alternatives.
Bad Sata Port (or Cable) Symptoms
The most common symptoms are the easiest to diagnose and are very similar to a hard drive failure:
- The hard drive is not found – it is not shown in BIOS and/or you see ‘No operating system found’ message at startup so Windows will not load.
In this case the problem is likely to be a faulty hard drive or SATA cable or else the port itself (the SATA controller) is bad. See the next section for ways to test which of the three is the cause.
But the symptoms are not always so obvious, as a PC that I worked on recently shows – it was 4 years old and worked fine most of the time but suffered from:
- Occasional blue screen of death (BSOD) crashes
- Random long freezes – sometimes followed by an automatic shut down and restart
These issues had been getting worse for 6 months and now averaged about once a day – but with no pattern as to how long the PC was on for or what software was in use at the time…
All these types of error can be caused by a hardware or a software problem – and, being intermittent, they’re not easy to troubleshoot.
Diagnosing An Intermittent Faulty SATA Port
I first backed up all the important documents and files – really important if hardware failure is suspected e.g. if a hard drive is dying then testing it might just finish it off…
1. I checked Event Viewer, looking particularly at the System logs for relevant errors. Several errors typically relate to memory (RAM) faults so I tested the memory – no faults found. (If the problem was not so intermittent I could have just swapped out the RAM to test it)
2. Other errors in the logs typically relate to hard drive faults – although they could also have been due to all those unexpected shutdowns corrupting the Windows file system. As the PC was 4 years old I tested the hard drive to see if it was failing – no faults found.
3. A faulty PSU (Power Supply Unit) can also cause random freezing and restarts so I tested it under full load – no faults found.
So far I had established that the hard drive, RAM, PSU and temperatures were all fine – there were no other separate components (like a graphics card) so this narrowed down the cause to an intermittent motherboard or SATA port or SATA cable fault – or software errors.
The biggest issue was not being able to reproduce the error – even under stress testing the PC had remained resolutely stable with no crashes or freezing.
Unless I could find a ‘smoking gun’ I couldn’t justify the time needed to update drivers/software, and certainly not the cost of replacing the motherboard or writing off the PC – I needed to make this PC crash!
- My experience pointed me towards heavy file read/write access causing related memory and hard drive issues, hence the crashes/freezing…
- So I ran a full virus scan (also useful to rule out viruses) which would read/check every file but it found no issues – and still no crash.
- Finally I decided to do a full disk cleanup – it froze half way through and the PC shut down!
- To make sure, I tried a few disk cleanups in both normal and safe mode and the PC froze up every time.
At last I could reproduce the problem at will so I could be confident if a repair was successful.
First I tried a new SATA cable for the hard drive – disk cleanup still crashed.
I then moved the hard drive SATA cable to a different SATA port on the motherboard – and disk cleanup finished successfully :-)
I repeated the test by trying a few disk cleanups in both normal and safe mode and they were successful every time – no freezes at all.
As a final check, I moved the SATA cable back to the original port on the motherboard and, sure enough, disk cleanup started failing again – proving for certain that particular SATA port was bad. Job done!
How to Fix Faulty SATA Port on Motherboard
Realistically you can’t fix a bad SATA port, only work around it – the SATA controller is an integral part of the motherboard. So if you have a laptop, sadly you’re out of luck – it will likely need manufacturer repair or replacement of the motherboard.
But in a PC you can work around it, as the Repair section above shows – if you have a spare SATA port, move the hard drive SATA cable to use that instead and all should be well. If the SATA cable itself is faulty, replace it with a new one.
If you only have 2 ports and both are in use (1 for the hard drive and 1 for a DVD drive), unplug the DVD drive and use that SATA port for the hard drive instead. If you really need a working DVD drive you can buy a cheap external USB DVD rewriter, check price at Amazon.
What If All Motherboard SATA Ports Are Faulty?
This is more likely if you have an older PC or only 2 ports. Possible solutions include:
1. If you have a free PCI-e slot, add new SATA ports by installing an internal card like this PCI-e card, check price at Amazon adds 4 internal SATA ports. Note that you may need to reinstall Windows to get such ports working for use on the system (Windows) hard drive.
2. Replace the motherboard.
3. Buy a new PC – note that as long as the SATA hard drive itself is not faulty, you could reuse it in a new PC.
Or retrieve your data from it and use it as an external USB hard drive by buying an external USB SATA hard drive enclosure, check price at Amazon. You need a 3.5 inch enclosure for a standard size PC hard drive – 2.5 inch enclosures are for most laptop and SSD drives.
In my example, the SATA port (disk controller) on the motherboard was faulty – but only intermittently and under heavy disk activity.
This is a rare outcome – the usual symptoms of a faulty SATA port are that the hard drive is not recognized in BIOS or Windows does not load, producing disk read errors or a ‘no operating system found’ message.
It underlines the importance of thorough step by step testing – and being able to reproduce a fault so that you can test if a potential fix actually works, otherwise you’re just shooting in the dark…