New Business Laptop from Hewlett-Packard, HP ProBook 6550b/CT and HP ProBook 4420s/CT. Both of Laptop has a Gigabit Ethernet, ExpressCard/54 slot, D-Sub, a 3.5mm audio jack, and up to 4.5 hours (4420s) andup to 5.5 hours of battery life (6550b), with weight around 2.14-kg. The HP ProBook 6550b/CT comes with Intel Celeron P4500 (can upgrade to Intel Core i7) Processor, 15-6-inch widescreen LCD display with 1366×768 pixel resolution, Intel HM57 express chipset, 2GB of RAM, 250GB of HDD, DVD drive and pre-loaded Windows 7 Home Premium 32bit OS Whereas HP ProBook 4420s/CT powered by Intel Celeron P4500 processor, a 14-inch widescreen LED backlit display with 1366×768 pixel resolution, Intel HM57 express chipset, 250GB of hard disk drive, 2GB of memory, and pre-Loaded with Windows Vista Home Basic OS.