Comment by jstanley | Hacker News Reader

Comment by jstanley | Hacker News Reader

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Computers do do this. The problem is that some computers are quite old and the battery that keeps the real-time clock running has gone flat. That means if the computer is powered off it forgets what time it is.

If your quartz watch battery goes flat you replace it straight away because a watch with a flat battery is 100% useless. But if the battery on your motherboard goes flat you don't even notice, so why would you replace it? To a layperson, "my computer's time is always wrong" is not likely to be caused by a random flat battery that they didn't know existed.

Microsoft came up with this "Secure Time" system so that even computers with flat batteries would be able to work out what time it is, but obviously it is kind of weird and sometimes makes wrong decisions.

Fixing computers with a broken batteries sounds just about as smart as

"Microsoft came up with an internet boot image that allows your computers to boot windows even if the hard drive is dead without users realizing this is the case"

Honestly, when the battery dies, it's time to take it to the shop.

Timepieces last a decade on a shirt button sized battery. Surely you can afford a bit larger battery on a motherboard, probably even a rechargeable one, make the clock sufficiently autonomous from the rest of the system, and make the motherboard not boot when it doesn't have the battery, so you can leave it unattended for a while.

The CR2032 on a PC motherboard does usually last for about a decade, and the BIOS (or, well, UEFI) will scream about the CMOS battery being dead when you boot it. It will not refuse to boot, but it will tell you that the battery is dead and/or that its settings are corrupt and alert you to change it.

A decade is roughly the upper limit of specified battery shelf life for cheap batteries. Making the battery bigger doesn't really help much at that point where it's limited by shelf life, not capacity.

There are longer life batteries, but they're _expensive_, e.g. a Tadiran TL-4934, 1Ah, with a shelf life of 40 years will cost ~5$ in bulk.

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