I'm sorry, but that's simply hearsay. I use a PC and I regularly do Photoshop/Lightroom work on it, as well as some gaming and a distributive computing program called Folding@Home, and my PC is rock-solid stable. It stays on for weeks at a time with no issues whatsoever, and the only reason it can't go longer than a week is because I have to restart the PC for system updates.
This is a screenshot of my current PC running. So far it's been 9 days since the last restart, and that was only because I was out of town and didn't want to leave my PC on for no reason. I've had three heavy LR/PS sessions, four gaming sessions, and F@H running in the background 24/7. And of course, the usual internet browsing/music/video/office tasks.
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