Windows 10: DDR3 question

I am wanting to upgrade/add memory to my laptop and I am in confusion as to all the different types of compatible memory available.

My system requires: DDR3 PC3-12800 • CL=11 • Unbuffered • NON-ECC • DDR3-1600 • 1.35V

You'd think that the above specifics are just that; specific. Why so many different cards available? Why the vast difference in price for a card with the same specs? What's the difference in all of them?

Does it come down to the more $$ the more you're getting even though they appear "the same"?

Thanks in advance.

:)

 

Windows 10 RAM Upgrade

I have a question, that if I wish

to add another 4GB DDR3 RAM in the

second slot of my PC, (the first one has

4GB DDR3), then according to Windows 10, will

my version be deactivated due to this hardware change?

Thank you for your concern.

 

Windows 10 retail license key

I've been looking into possibly getting Windows 10. I found retail license keys being sold on eBay for extremely cheap (under $15). It
seems like there would have to be some issue with these. However, I'm not sure what the problem could be. I've been doing some research. If I understand correctly, if it's retail then it cannot be OEM. Also, if it's retail, I understand it cannot be
a volume license key. From what I understand, it cannot be MSDN, either. If it were simply pirated, then I don't see how it could be activated as they claim it can be. What am I missing? FWIW, it comes from Europe, but claims to be valid worldwide.

(Not linking to the eBay sale as I don't want to "promote" it if there is an issue with it. But what can you suggest to me based on the little info available?)

Edit: A possibility... could it potentially be resold to other parties and activated by them, but then if I reinstall (when enough activations have been done), I will be unable to reactivate again?

 

Memory is like most things there are only a few manufacturers for the chips on the board and a whole bunch of builders, just stay within the specs of your MB (204 pin DDR3 1.35V). I always go with lifetime warranty, same mem chips in all slots, equal timings and lower CL and buy all the GB affordable. Crucial, Kingston, PNY, and Wintec are good choices. Be careful to compare the specifications they are generally the same, check the manufacturers website for better details. More $$ only gets more capacity and speed, unless it is a OC/Gaming rig them it gets more complicated and expensive. Hope this helps.

 

Thank you. That did help!