The first bad sign is someone telling you "mainframe." That's a poor term to use.
There are free computers on FREECYCLE and Craigslist as well as help like this link.
If you don't fix your own PCs there are ways to gain access.
I have a Dell Inspiron that I was told that I fried the main frame on - How I have no idea how I managed that! (I do have all the disks etc)- it is approx 9 yrs old. I used it very little. I am now getting Internet again at my home ( been 7 yrs since I last had it). Is this computer worth trying to fix or having someone look at? I am Very Poor and Not computer savvy at all. I do not want to pay to have someone look at it if it is best to just consider it toast. Thanks in advance for any help! .....Jack O