You can get them for anywhere from $25 and up. Mine cost about $55 if memory serves. Amazon has hundreds of models. When you get these short power outages, the battery provides the power to the computer until the power kicks back in. A lot of them come with a USB connection to the computer with software to automatically shut the computer down if the outage is starting to drain the battery. I wouldn't be without one.
Good luck.
Hello,
I recently installed a new CPU fan because the old one malfunctioned. But now that I have a new CPU fan installed my computer won't work properly. If I leave the computer on for an extended period of time (say a couple hours), the entire house gets a sort of mini power outage. The power outage doesn't last a second and everything comes back on quickly, but my computer then only has a blank monitor screen. I could type or click anywhere but the monitor acts as if it isn't receiving anything. I have to manual turn it off by unplugging the computer in order to shut it down as pressing the button on the desktop doesn't turn it off.
What could be going on?

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