With used PC`s You have to know the model numbers of the main parts so that you can age them and determine the computers value.
Its useless to know that it is i7 / 16gb RAM.
You should know what year was the i7 released and if it is DDR3 or DDR4 RAM.
What resolution is the screen.
I vote not worth it
Wont be that long before a new version of RAM is released called DDR5.
Current DDR4 machines are already dead in the water like what happened with DDR3 machines on the release of DDR4.
Nobody wanted DDR3 machines, they were finished, All you heard about on forums was...
Review here of that combo together.
Sounds as i would have expected :
Review Canon 50 mm f/1.8 STM @ 5Ds - CameraStuff Review
At full aperture, the contrast is low, and even the center sharpness clearly has room for...
There is nothing much you can do except use a tripod and use most optimal setting you can to gather as much light as possible without pushing ISO so much that it ruins the image.
Old problem that has no magic trick, but clever editing and good equipment help out a great deal.
newer ones are getting more read/write durable i believe. It depends how much they get used among other things.
I find modern PC`s highly reliable. I could sell you an XP system PC with all original parts no problem