#pc xt

Magic Smoke

I have a project I'm working on that needs an XT class machine, preferably at the original 4.77MHz.

I have an original IBM 5160 motherboard. It has a tantalum capacitor that is a direct short on the power supply. I also have an XT clone motherboard that I've successfully tested and booted a number of times.

I recently acquired a nearly complete XT clone system, but it was a 10MHz turbo XT, and missing its CPU. So I installed the known-good 4.77MHz XT clone board in the 10MHz clone case.

Flipped the switch and nothing happened. The power supply clicked like a switch mode supply failing to start up, so I quickly turned it back off. As the supply's capacitors slowly discharged, it continued its death click until ...

Pop goes the magic smoke.

I suspected the power supply at first. I've not had it as long, and those Rifa input filter capacitors are notorious for blowing at random times. Inside of the supply was surprisingly clean. No sign of damage, and thankfully, no sign of Rifa.

So turning attention to the motherboard, I found the culprit — a 16V tantalum filter capacitor across the 12V power supply. These too are notorious for blowing at random times.

This is the IBM PC XT, this was my first vintage computer that i have ever owned. this is a very important computer to me because i use it to learn the basic programming language that is built into the computer. I was attracted to this computer because i have seen it in many movies and it was the second IBM personal computer in history. I purchased this computer on eBay and fully restored it except I replaced the hard drive with another floppy drive. this computer is exceptionally important to my computer literacy because I have used it to understand the bare minimum that a computer needs to operate and be a functional piece of technology. This computer has also taught me that you don't need a super new computer to do the every day things on the internet. even though this computer is from 1983 it is fully capable of going on the internet and doing what any modern computer can except watch videos. This is pretty amazing considering this computer is now 31 years old. I also am using this computer to get a better understanding of the operating system and how it works on a hardware level. This information is helpful because I am working on building a computer from scratch. these are all the reasons that this computer is very important to my computer literacy.