If it's a working computer the I will use a profiler such as CPU-Z.
If not working or just plain loose hardware I start looking for brand names and numbers and use the trial by error old school method of online search which generally will give me what I want to know.
I have sometimes just connect a power supply / memory sticks / monitor / keyboard / mouse / hard drive and dvd rom and if needed install a processor and run a Linux Distro live dvd and use the terminal command sudo lshw > lshw.txt which will give more information than I need.
Takes a few minutes sometimes but worth effort as I then really know what I have.
I'm grumpy because I can be not because I'm old.
The world is what you make of it, if it doesn't fit, you make alterations.
Under certain circumstances, profanity provides a relief denied even to prayer. (Mark Twain)