Browsing and streaming no issues. Or any other daily computer task, all fine. No weird behavior, lags or freezes, nothing.
I've checked the source files, they're ok. I've even downloaded them from another computer, and transferred them on the Thinkpad with a USB stick, and they can be opened normally. Downloads are coming from various websites, a VPS, a local server.
badblock run
I'll do that now.
Thanks for the help!!!