R7800 restarts

Problem: 2-yr old R7800 router randomly reboots every 3-5 hours.
Solution: Replace the factory power supply (12V 3.5A) with a PWR+ Model PWR-TAJ120500 (12V 5.0A).

Starting around Thanksgiving, my Netgear R7800 router started to randomly restart.

As December wore on, the reboots occurred more and more frequently, eventually reaching once every 3 hours.
That's at least two restarts every workday.

The firmware had NOT been updated, so it wasn't a botched update that caused the problem.

Without the router loading the power supply, the original power supply measured 12.27V with 20mVrms ripple.
12.27V is a bit far from the 12V target, but not quite enough to say there's obviously a problem.
If it had been low by the same amount, say 11.73V, the need to replace the supply would have been more obvious because the voltage usually sags under load.

However, I've noticed that a poor power supply is a frequent hardware cause for flaky PCs, and took a gamble that the power supply was to blame.

Several advantages of the PWR-TAJ120500 over the original and other replacement power supplies are:

1. Braided/foil shield on the power cable with a ferrite bead at the router connector filters out electrical noise picked up by the long power cable.
2. More current (5A) available if the original power supply wore out because it was slightly underpowered for the R7800
3. Laptop-style brick + power cord means the plug only takes one spot on an outlet strip
   I should point out that Netgear's clever original supply is a slim and tall rectangle designed to plug in sideways, so it also would only take one spot, but most replacement supplies do not follow Netgear's design.
4. U.S. company, with the power supply manufactured in Taiwan.

After installing the new supply, there have been no restarts for over a week. Problem solved!

For the curious, the PWR-TAJ120500 measured 12.14V with 15mV of ripple without the router connected. A lot less noisy, and closer to 12V.