Available with 4th-gen Intel processors and Intel HD graphics 4600 or AMD HD Radeon HD 8750M discrete GPU, HP calls the ProBook its "most configurable" line of laptops. Unveiled today are the 14-inch ProBook 640 G1 and the 15.6-inch ProBook 650 G1, which are identical in almost every way except for screen size and number of USB 3.0 ports (the 650 has four, one more than the 640). Like the EliteBooks, ProBooks include spill-resistant keyboards with drain and tools-free servicing. They come with HD displays and are available with as much as 16 GB of RAM and 1 TB of spinning HDD storage or 256 GB of SSD with encryption options. Interestingly, ProBook units also still come equipped with an RS-232 port and optional modem port. According to a company spokesperson, this caters to specific types of users. "Many of our vertical market customers still use the serial interface to connect to specialized equipment," said the spokesman at a confidential media briefing prior to the announcement. Auto service and health care industries were given as examples. Availability is set for November with starting prices at around $699; exact pricing was not disclosed.