While I like Windows 10, this laptop would need a lot of drivers and apps to get it up to speed and working right. You have the i7's graphics driver which I think Microsoft might get right but them the 840M would require more help with drivers for chipset (motherboard) the latest Intel graphics and then what HP supplies for the 840m.
You also have the issues of a high end laptop to contend with. You must be using the canned air on the vents every 1st of the month or it may start to have issues early.
Then it's a HP. My last HP was my last HP as HP could not correct a flaw in their laptop plus making it worse in their repair center. Sorry HP but you lost me here since what person could withstand 6 months of a dead laptop under warranty by your service center's own doing.
Longer story at http://www.cnet.com/forums/discussions/laptop-buying-advice/#post-da7ca992-025a-4773-9086-f1d443e405ef
HP no longer engineers their products so when you find a product defect, they can't fix it. Best to exchange it for another model.
I have a hp notebook with windows 8.1 as standard. Recently, while browsing the internet, my notebook got infested by virus, and i had to uninstall it. What i did afterwards was, purchased windows 10 pro and installed it, but it didn't run quite well. I did every windows update and every driver installation from HP, but it didn't go good. The major problem was that it always refused to wake up from the sleep mode. The power button would be glowing every time, but pressing the keyboard or the power button wouldn't do a thing. The screen would be dark and i had to power it off forcefully by long pressing the power button and power it on again. Similarly, it didn't shut down properly. As the power button would be glowing without the notebook shutting down, ever.
So, considering these setbacks, i reinstalled windows 8.1 with the default product key, and now after several updates, i have a windows 10 upgrade icon displayed at the task bar. So, if i do the upgrade this way, will i have to face all those similar problems ?
Should i do it, or not ?
Here are the specifications. Hope hardware wasn't the cause for windows 10 not running well.
Microprocessor 2 GHz Intel Core i7-4510U with Intel HD Graphics 4400
Microprocessor Cache 4 MB cache
Memory 8 GB 1600 MHz DDR3L SDRAM (1 x 8 GB)
Video Graphics NVIDIA GeForce 840M (2 GB DDR3 dedicated)
Hard Drive 1 TB 5400 rpm SATA.

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