Kobalt G860 Laptop Review

Specifications

This was the first laptop we'd seen with one of the new Core i7 Mobile chips, and with Nvidia's current top-end GeForce GTX 280M graphics card also present inside, we were expecting some high frame rates for the reasonable sub-£1,500 price. As we mentioned, there were Core i7 laptops before this, but they used desktop chips and were the size (and weight) of concrete paving slabs.

The Core i7 Mobile series spans three chips that were designed to be squeezed into a foldaway PC. Kobalt has used the entry-level model, the Core i7-720QM, which has 6MB of Level 3 cache and a nominal frequency of 1.6GHz. The 820QM has 8MB of Level 3 cache and a nominal speed of 1.73GHz, while the 920XM Extreme Edition also has 8MB of Level 3 cache but a nominal frequency of 2GHz..


We say 'nominal frequency' because not only does the Core i7 Mobile have the usual SpeedStep technology to lower the multiplier (and therefore the overall frequency) when it's not working hard, but there's also Turbo Boost technology to increase the multiplier when the CPU is working on single-, dual- or even eight-threaded applications. We saw the 720QM in the Kobalt clock itself at anything from 933MHz (with a 7x multiplier) to 2.79GHz (with a 21x multiplier).


If you wanted proof that the gigahertz war was over, this is it - it's all but pointless to talk about these CPUs in terms of a rated frequency. Apart from the differences in Level 3 cache and maximum Turbo Boost frequency, the three Core i7 Mobile CPUs are fairly similar. All three have a dual-channel memory controller and can address up to 8GB of DDR3. All are quad-core, all support Hyper-Threading (so can process eight threads in parallel), but while the 720QM and 820QM have a low TDP of 45W, the 920XM has a TDP of 55W.


Elsewhere in the G860 there's the PM55 chipset, which tells us that this new range of Core i7 Mobile CPUs is based on Lynnfield rather than Bloomfield. There's 4GB of 1,066MHz DDR3 memory and a 500GB Seagate Momentus 7200.4 hard disk, which spins at 7,200rpm. You'll also find 802.11a/g/n WiFi, Bluetooth and Gigabit Ethernet.

Scattered around the case are four USB 2 ports, eSATA and mini-FireWire ports, and HDMI and DVI outputs. There's an ExpressCard slot and a 7-in-1 card reader for SD, MMC and Memory-Stick cards. The rugged plastic body of the G860 has little flex or bend and will handle a few clumsy knocks without much problem; the lid is bendier, though.