ive just recently started mining bitcoin im just running it off of an a4 laptop with a radeon hd 7420g gpu.ive researched a couple asic miners looked at an external box and a usb erupter i have 2 questions what would make mining efficient on my computer and im wondering if i have acces to 50 computers if i run miners on all of there cpus would that total up to anything close to running a single erupter on my laptop