A decade old PC, years of Windows 11 startup crashes, and the 1 pound part that fixed everything

[CosmicRay65]

Posting this partly as a confession and partly as a public service, because if it saves one person the journey I went on it was worth typing. My PC is over a decade old and ever since I upgraded it to Windows 11 it crashed regularly on startup. Some days it would get a quarter of the loading circle on the Windows logo, other days just a black screen of death, and then the daily ritual of Windows attempting recovery only to crash again at setting up repair

I tried everything, and I mean everything. BIOS update, cleaned the whole machine inside and out, swapped the old HDD for a new SSD, added more RAM, added more fans in case it was thermal, full Windows reinstall, system restore, the lot. Every fix bought a little hope and none of it stopped the crashes, and at times it was genuinely painful, you start doubting the whole machine

The culprit, in the end, was the CMOS battery. A part that costs about one pound, in a PC I have owned for ten years. The cruel twist is I had a couple of spare batteries in the drawer and tried those too, and it turns out they were ALSO dead, which is exactly what threw me off the scent for so long and then finally told me what the problem was

The working battery that solved it came out of a clicker I use for taking pictures on holiday, of all places. Dropped it in, and no crashes since, no more daily recovery attempts, no quarter circle of doom, just a boring ordinary boot every single time. Pictures of the patient and the tiny hero attached below

So the lesson for the thread, when you have ruled out the software side and it is not Windows update related, and you have ruled out the normal hardware suspects, check the stupid cheap thing before you spend another penny. I now have a new battery, a working PC, and a fortune saved on the replacement machine I very nearly bought. Anyone else been defeated for months by a part that costs less than a coffee?

[Myles95]

The dead spares are the killer detail, you did the right test and the test lied to you. That is the kind of luck that adds months to any diagnosis

[Grim Tracey]

Classic CMOS gotcha, when it dies the board forgets its settings every power off, and if it had anything non default saved, boot order, memory profile, the whole startup goes haywire. The pound coin battery takes down the thousand pound machine

[Leah_68]

Genuine question, did you not notice the clock resetting or BIOS settings going back to default? That is usually the tell tale before the crashes start

[SlowSocket]

Not always, if the machine stays plugged in at the wall the battery can be half dead for ages and only fully show itself in weird intermittent ways. The sneaky failures are the half dead ones

[RayOfLight32]

The battery from the holiday clicker is the best part of this story, somewhere a little camera remote made the ultimate sacrifice for the greater good

[SpinState52]

Been there with a different cheap villain, weeks of blue screens that turned out to be one SATA cable that had gone bad. The cheap parts fail quietly and let the expensive ones take the blame

[Georgia67]

In fairness the journey was not wasted, you came out the other side with an SSD, more RAM and better cooling, the crash was accidentally a full upgrade programme

[VoidRanger40]

This should honestly be a sticky, CMOS battery is step one on any machine past five or six years old and almost nobody checks it because it seems too small to matter

[QubitZero]

I would not make it step one myself, a dying battery causing full startup crashes rather than just settings amnesia is the less common version. Worth checking early because it costs a pound and a minute, but it is not the usual suspect

[Evan0]

That is exactly why it costs people months though, everyone including the internet tells you it only resets the clock, so it never gets tried until desperation sets in

[Holly]

Looking forward to the pictures, there is something properly satisfying about a photo of a ten year old tower back from the dead next to the coin sized part that nearly killed it