The Core i7-640UM's biggest selling point, though, is that it couples this fine performance with Turbo Boost to give the cores a temporary boost to 2.266GHz, Hyper-Threading to bump up the number of cores from a physical two to a logical four, and an extremely low power draw. This processor's TDP is an incredibly frugal-looking 18W.
This leads us, however, to the J3500's major weaknesses battery life. Despite boasting twin packs, the batteries that slot into the bays at the rear of the device are low on capacity (2,000mAh each), and it shows when you come to use them away from the mains. In idle with the screen on half-brightness, they lasted just four hours 39mins before both ran completely dry. That's disappointing, as each mobile worker will need at least one spare battery pack to get a full day's use and, therefore, the desktop battery charger accessory too.
The price softens the blow. In its most basic configuration the J3500 starts at 1,620 exc VAT, going up as you add to the specification until you reach our review model at 2,253, but even at that price it's good vale for a mobile computer this rugged. Dell's XT2 tablet, for comparison, although a little more water resistant, starts at a base price of 2,534.
But still, we find it rather difficult to wholeheartedly recommend the J3500. It's supposed to be a no-fuss, field computer, and it certainly has the feature set to go the distance, but its small batteries and inevitably limited battery life damage the convenience and manageability from both an end user and IT manager's perspective, and just hold it back from achieving greatness.
Verdict
A versatile and reasonably priced rugged tablet PC, but the battery life is a little disappointing.
Processor: Intel Core-i7 640UM, 1.2GHz
?Memory: 4GB 800MHz DDR3 RAM?
Graphics: Intel HD Graphics
?Hard disk: 128GB SSD
?Display: 12.1in 1366 x 766, LED-backlit, sunlight readable, Wacom dual multitouch and digitiser screen?Features: Three megapixel camera with light, fingerprint reader with TPM 1.2, microphone, stereo speakers
?Connectivity: 802.11a/b/g/n Wi-Fi, Gigabit Ethernet, Bluetooth 2.1 + EDR?Ports: 2 x USB, D-SUB output, SmartCard slot, ExpressCard/34, 3.5mm headphone and microphone audio sockets ?
Dimensions: 323 x 231 x 23mm (WxDxH)?Weight: 1.9kg?
Warranty: 1yr C&R warranty?
OS: Windows 7 Professional 32-bit
