XPS 8900, CMOS battery plastic tab broke

They are sorta correct, the proper fix is to have a new holder soldered-in.

However, I surely would not suggest you make this your first try at soldering. Someone that is skilled in board-level repair and soldering will need to do that for you. Even getting the old one out/un-soldered will be tricky because that is a multi-layer PCB motherboard. One slip-up, pulled-damaged trace, etc ... and you have killed it forever.

You can also replace the motherboard. Problem is, this machine is not validated to run Windows-11 (so why bother). Also, be sure you know your existing OEM Windows-10 key , as some OEM-replacement motherboards don't come with another one.

Finally, even with a cracked plastic holder ... as long as the 2 metal parts are still there and soldered into the motherboard underneath ...

AND the coin battery seems to be staying in place and doing it's job ...

... I would not mess with it. Machine is 10 years old. Use it and plan on getting a newer Windows-11 one.

Tesla gave a thorough reply.  I would add that you can also just run the pc without battery as long as you keep a power cord plugged in wall outlet all the time.  The 5VSb power even when pc is off can sustain CMOS settings.  if in case you need to unplug, when reconnected to power just reset the date time.

Well, there are two plastic tabs in the holder, and it appears to stay in with just one, but I put electrical tape on it just in case.

Paying good money to replace a perfectly-good computer with one with a worse version of Windows just doesn't make any sense.

I look forward to Microsoft no longer rebooting my computer without permission even though I told them not to several different ways.

As I mentioned in my other thread, I am in grad school.

I only started troubleshooting this one after buying a new computer, which happens to be an Inspron--and I returned.

I had just wanted to swap over the video card I bought for this computer a few months earlier and its hard drive, but that computer isn't designed to be upgraded at all, so I paid $100 more for one with the same video card I have in my 9-year-old Dell (and a bigger power supply--and half the RAM), but I had all kinds of problems with it.

The screen randomly cuts out, which isn't a problem with my old Dell, or my laptop when I connect it to my desktop display and peripherals.

When I started setting up that computer, I randomly couldn't install more programs, and I forget the drama, but I ended up reinstalling Windows on a new computer.

I still haven't figured out how to make win10 allow me, the administrator, to download files to my Download folder.

The second Inspiron needs to go back, too, so I bought the only other desktop Costco had, a CyberPowerPC, which was all right once I figured out how to turn out the lights.

Since Microsoft doesn't care what we want, that woke up my wife and I in the middle of the night with lights that even lit up the bathroom--and helped trigger a migraine.

I fixed my XPS, though, so the gaming machine is going to a gamer.