It depends on air humidity if anything.
For example, in tropical parts of the world, the humidity is high all year round. Or when you live next to sea. Then, there is more wear on the hardware and after some years, you can actually see rust forming on PCB (GPU/MoBo).
Winter weather, for the most part, doesn't have much humidity outside. Sure, it's cold outside but humidity levels are usually low. Now, if it would be summer time with rainfall, then humidity would be higher.
Then, there's also humidity levels in your home. That depends on the house you live in and ventilation system it has. But for the most part, air inside homes is usually low humidity. If the inside air humidity drops way low, then you could start having breathing problems or your eyes could start hurting (since dry air dries out your eyeballs, especially if you don't blink often when watching PC monitor for days end).
For condensation to form, there needs to be extremely high humidity.
Prime example would be car and car windows fogging up. This usually happens when there is high temperature difference between outside of the car and inside of the car + the humidity inside the car is higher than outside.
To avoid car windows to fog up, in summer time, you cold open car window a bit, to normalize temps between outside and inside. But during winter time, this isn't an option since idea is to get the inside of the car warm and comfortable. But you can then activate car AC (if your car has it), since besides heating up air inside the car, AC also collects humidity from inside the car (which it then drops under the car).
Back to your initial question about humidity inside the PC.
Unless PC has sat inside humid conditions (~80% humidity) for too long and you then turn on PC, with high heat output (e.g start 3D render at instant), there are no other possible ways to collect condensation inside the PC.
Running your PC at winter time with window open won't generate any condensation since air humidity would be low. If anything, outside cold air helps to better cool your PC components.
But if you are worried about condensation, you can buy silica gel packs. Usually some clothes come with small silica gel packs packed inside them, but buying bigger silica gel sack would be better.
Just the other day i was browsing my local car parts store and saw them to offer several sized silica gel sacks (320g, 500g, 1kg) to be used inside the car (or anywhere where there is high humidity). I did think getting one, since during winter times, my car windows sometimes fog up. Some of those sacks also had indicator on them, showing when they are "full" of moisture, so that i can take the sack and put it into dry place (e.g on top of radiator or inside microwave) to dry out, after which, i can put it back inside the car to collect moisture again. So, quite practical.
This is the very one i did consider buying,
amazon:
https://www.amazon.de/-/en/Relaxdays-Set-car-defogger-sponge/dp/B0827MWFLX
And considered this one too, with more practicality by having velcro straps to hold it in place, but no "full" indicator,
amazon:
https://www.amazon.de/ProPlus-240214-Luftentfeuchter-Autoentfeuchter-wiederverwendbar/dp/B003F5RKHI
But since car windows fogging up isn't that much of an issue for me, i didn't buy it. Maybe in future, i need to think about it.
🤔
As of you, you could put the silica gel pack/sack inside your PC, if you're that worried about condensation.
Oh, probably best way to tell if air inside the PC is dry or not, is to look if any fine dust settles on your components. Since air must be dry for fine dust to settle down. If air has high humidity, you'd see dust bunnies (balls of dust), rather than fine dust blanketing the surface evenly.
There are other GPU support brackets as well.
Facebook
Twitter
Instagram