Elitebook 8540w cpu upgrade

[_Rici_]

Hello i have Hp Elitebook 8540w with dualcore motherboard and want to do quad core cpu upgrade on it ( i7 920XM). Some are saying it is not possible and some are saying that it is working. Can someone confirm that i can install a quad core processor in it ? 

Thank you. 

[Jupitero]

Hello.

According to the Maintenance and Service Guide for 8540w, you laptop lists four different quad-core i7 processors as compatible, but 920XM is not one of them.

The best performing compatible processor is i7 840QM, which is practically identical in performance with the older 920XM, with only slightly lower base frequency, but same Turbo clock.

While a 920XM will physically fit into the CPU socket, it has a power draw requirement of 55 watts, whereas the supported CPU's are all 35-45 watt models. It is therefore very much possible that the system board and power circuitry was designed to only support 45 watt models. The cooling system may also be unable to cope with the extra heat the 55 watt CPU can produce. Your battery life will also suffer somewhat. Finally, your laptop may still produce an error message about unknown CPU model or just fail to boot with it.