would like to replace sata cable new battery and replace the hd with an ssd drive 500gig or 750 or what do you all reccommend-it is very very slow.....other than that works fine.- it is my backup but needs to be faster to fulfill that purpose.thanks
Replacement of the hard disk drive is very easy. Suggest you purchase a 512GB or 1TB SSD, preferrably a Samsung SATA II or a SATA III, and a very inexpensive USB 3.0 drive enclosure. Plug the SSD into the USB port and clone the internal drive to the new SSD using the MacOS Disk Utility. Check Youtube for videos on cloning drives.
Everything you asked for is in the thread, "2012 mbp way too slow?!" The SSD is easy, as is the battery, but take it slow when replacing the SATA cable.