Repairing a DS1515+, Intel Atom C2000 Woes [Tutorial]

Repairing a DS1515+, Intel Atom C2000 Woes [Tutorial]

January 12, 2024 08:54 EST • Alexandre Vallières-Lagacé • 6 minute read

One of the worst things to happen to a Geek’s setup is to see it fall down to pieces. This is exactly how it felt when my Synology NAS gradually started giving up on life.

The Rise of the DS1515+

The DS1515+ is a 5-bay NAS from Synology that has the extra powerful CPU (for the time), an Intel Atom C2538 Quad Core 2.4GHz, part of the C2000 series CPU, an information that is important. It has extra memory banks and was one of the first to get the SSD Cache feature where you could add an SSD and it would keep regularly accessed files there for faster retrieval.

I got mine in April 2015, quickly set it up and started making it part of my home network. It was wired and accessible to every TVs in our house, and I could copy files to it quickly through Ethernet. If I had a big dump of data to do, I could use the USB3 port and quickly copy files over.

Then, in January 2016, I had an idea. Let’s pimp that NAS! So I got together with a few great companies and wrote a blog post on how to customize this NAS and really pimp it up!

I added a 4GB RAM module from Kinston, on top of the existing 2GB that came with it. A brand new Kingston SDD to act as the SSD Cache. Two new Noctua NF-A8-FLX 80mm fans, so that I can now run it in “Cool Mode” but has it generate less sound than the regular mode with the original fans!

All that was great, until last fall… Almost 8 years to the day.

The Downfall of the DS1515+

This NAS has been rock-solid for me. Running 24/7 and always being there, with very few issues over the years. Most of the issues happened near a power outage or a sudden OS upgrade I was not expecting.

But then, it restarted itself. Once, then twice. And the third time, I manually held the button to tell it to power cycle, and it never came back to life. Well, it was “alive” but the power LED was flashing blue, and the Alert LED, a LED I never saw ON, was also flashing orange. Oh, oh.

NAS in the Closet

The Research

Research online brought me to the famous C2000 problem. That generation of CPU from Intel has a known issue. So much that Synology added years of warranty to the product to cover for any issues, but there’s no real permanent fix. All you can do is try a few things and hope that one of them is fixing the problem. But none of them are permanent.

I listed a few things to do, with increasing levels of difficulty:

  1. Try software resets (with the reset button)
  2. Try to plug the disks in my computer to restore data
  3. Remove extra RAM, leaving only the OEM RAM stick
  4. Replace the CR1220 battery
  5. Add a 100ohm resistance
  6. Replace the BC847B transistor

The Execution

Steps 1 through 4 did not accomplish anything of meaning. Sure, I now have a fresh CR1220 battery in my NAS so that’s not a totally bad thing.

The Pain of the Data

The worst thing is step 2, when I tried to plug in my disks to my Mac. Not only can’t the Mac read ext4 disk outright, but even with the proper filesystem support added, I still needed the full-disk array plugged at the same time. This means all 4 SATA HDD must be plugged at once, including the 5th SSD Cache. And then, expose this to an Ubuntu virtual machine…

This means that, spoiler alert, in the future if I really need to replace my Synology, I absolutely have to swap it out with another 5-disk model. I can’t just get my data and move it to a 2-disk system for a while. This really is not fun and I am now thinking of getting a closet Mac Mini setup with Backblaze backed up disks to the cloud. So the data is always available, without the need to fuss with multiple disk arrays.

The Hunt and the Kill

Now that I had tried the easy steps, I need to get the 100 ohm resistance and try that. It’s far easier to solder this than to replace a transistor so let’s try that first. I found them on Amazon, 100 Ohm Resistors, 1/2 W, 5% (Pack of 10) for about 10$CA. My first order got lost and my second was cancelled. Sure it did not help that it was during the holidays, but still, it’s the first time Amazon is not able to ship me my order like that.

I then headed to the electronics store and was able to score 5 resistances for 23¢ 😄 I was then ready to do the installation. I used imagery found online to visually know which of the holes to use with the resistance and used my good old soldering iron to get this done. An easy job if you ever did soldering, and not a complicated one if you never did, just make sure the solder does not touch other contacts and you should be good.

The Boot Up

After the installation, I reassembled everything, easy task if you lay out your screws in little containers. I love the iFixIt anti-stack project tray, since it has lots and lots of little compartments for screws. It makes it easy to empty them in reverse order to get things back together.

Upon setting it back where it belongs, and hitting the power button, the NAS starts up… and no more flashing Alert LED! Success!

It’s Alive!

Heading back to the Synology admin panel, I can see it complained of a few unexpected reboots, and all, but everything is there and correctly configured. The date was wrong, but after a quick sync up with a time-server everything is good to go!


This is by no means a permanent fix. The C2000 line of CPU still has that hardware bug and we can’t get it fix. The only permanent solution is to replace the NAS with another NAS. The resistance will eventually give up, and we all have to use another one, and another one. I’m hoping this can last me a few more years, until I score a Mac Mini and replace my whole system with a closet Mac Mini with external hard drives.

There is still a chance that the resistor dies, and I will have to get that little thing fixed. Not as easy as these things are tiny, but it’s still doable with a magnifying glass and a more precise soldering iron. Let cross that bridge when we get there; we are not yet on that path.

Got some valuable information from these links:

Fixing a Synology DS1515+ not powering on
Synology: How To Fix C2000 Flaw With 100 Ohm Resistor