PGA988 - CPU Upgrade

[Craterloads]

Does anyone know what the best compatible CPU upgrade would be for the PGA988 platform.

I'm also worried about thermals, as the heatsink isn't much.

Currently it has an i4 350m installed, I know a i5 460m can be installed with no issues. I would like to install an i7 620m.

Since all the CPUs listed are 35w am I correct in thinking the thermals of them all will be similar / same?

http://www.cpu-upgrade.com/CPUs/Intel/Core_i7_Mobile/i7-640M_(PGA988).html

Core i3-330M - 2.133 GHz - 35W
Core i3-350M - 2.267 GHz - 35W (currently installed)
Core i3-370M - 2.4 GHz - 35W
Core i3-380M - 2.533 GHz - 35W
Core i3-390M - 2.667 GHz - 35W
Core i5-430M - 2.267 GHz / 2.533 GHz - 35W
Core i5-450M - 2.4 GHz / 2.667 GHz - 35W
Core i5-460M - 2.533 GHz / 2.8 GHz - 35W (Known works)
Core i5-480M - 2.667 GHz / 2.933 GHz - 35W
Core i5-520M - 2.4 GHz / 2.933 GHz -35W
Core i5-540M - 2.533 GHz / 3.067 GHz - 35W
Core i5-560M - 2.667 GHz / 3.2 GHz - 35W
Core i5-580M - 2.667 GHz / 3.333 GHz - 35W
Core i7-620M - 2.667 GHz / 3.333 GHz - 35W (want to install)
Core i7-640M - 2.8 GHz / 3.467 GHz - 35W

They are all dual cores with hyper threading so the i7/i5 moniker is a bit of a gimmick, the only difference being they turbo boost. But the higher end models do have a higher stock frequency too plus they don't cost much these days.

System is a Lenovo IdeaCentre A310 All in One

 

[Craterloads]

Edit: I think the i5 560m makes most sense price considering as can pick up for £15 on the bay whilst the i7 620m is £40

If the i5 460m works surely the i5 560m should work?