Hi Jeremy,
I order to replace the PCB for the Micro USB charge port you would have to replace the entire motherboard since the Micro USB and HDMI ports are directly connected to it. If you disassemble the T100 down to the motherboard though, you can look at the Micro USB port and determine if one of the 5 pins has broken the solder contact. This is the most common reason for this port to only work if you hold the cable in a particular position. If this is the case, it would be best to be extremely careful not to bridge the contacts and simply resolder the broken contact down. You could replace the port if you would prefer, but that would require you to desolder the 5 contacts to remove the old one, and then solder on the new one. If you plan to go that route, you can search on eBay for any Micro USB port that is meant to be mounted flat on the PCB. This is what you would need - [http://www.ebay.com/itm/Micro-USB-Charging-Port-Connector-ASUS-TRANSFORMER-BOOK-T100T-T100TA-Dock-Tablet-/331389783753?pt=LH_DefaultDomain_0&hash=item4d285ecec9|eBay: Micro USB Charging Port Connector]. If you wish to replace the entire motherboard it can range between $50-$100 USD, depending on the CPU and storage, and it should come with the eMMC Storage drive, Memory, and CPU already soldered to the board (these components are not supposed to be removed), and this is a link to a 32GB version - [http://www.ebay.com/itm/OEM-ASUS-TRANSFORMER-BOOK-T100T-TABLET-32GB-LOGIC-BOARD-MOTHERBOARD-ORIGINAL-/161695904622?pt=LH_DefaultDomain_0&hash=item25a5d3b36e|eBay: 32GB ASUS T100 Motherboard]. Let me know if I can be of any more help.