"You buy a laptop, and in three years when you see a better notebook, and you wanna sell the old one."
For a 3 years old laptop these day? If the case is not made of solid gold, no matter the CPU you'll be lucky to get 10 bucks and a bubble gum. Stop being a tosser, will you?
The only way you could get 10 bucks plus TWO bubble gums is if the CPU was server-grade (and then again, no matter the brand, joker), true ECC RAM, and a server-rated main hard drive.. And the odds of finding these in a consumer laptop are, erm, how to say that? RATHER small? A bit like the odds of finding an unknown wallet full of $200 banknote on your bedside table one morning. There ARE a few laptops around which still have a market value after 3 years, but they tend to cost the price of a car when new, and are worth a second-hand bicycle after 3 years, so if you can afford them you probably don't care about reselling them when you want a new one. Unless you're stupid enough to believe the greengrocers at PCWorld, in which case you probably also buy the 5 years warranty extension because your POS will be worth MUCH more in 3 years if there is still 2 years on the original warranty. Yeah, believe that, bend over and cough, please.
Plus anyone buying a laptop as an over-3-years INVESTMENT desserves to be tortured in the most gruesome manner. A laptop is NOT an investment. Actually a laptop is the exact OPPOSITE of an investment. If you want to "invest" in computer power get yourself a nice workstation in tower form, with plenty of room for expansion, nuke-proof RAM, a server-grade SSD as the system drive and whichever hard drive(s) you want for your data and custom applications (the thing is, DON'T store ANYTHING or even TOUCH the system SSD once the system is set up: the HDD with your data can be replaced for cheap, a good SSD cannot.) and the lot. THAT is an investment on the future. For, 15 years, let's say.
Anything lesser is a disposable device. I should know, I own and have owned a number of disposable devices, and I'm typing this from a non-disposable machine, 10-years-old, 2 GB shielded ECC RAM, 7200 rpm hdd for the system drive, Ultra Wide SCSI connection ( SSD and SATA were not available at the time) and 7200 rpm drives, Ultra Wide SCSI connection for the data (while I was at it...), 2x1GHz machine (that's two separate 1 GHz chips, in case you wondered. Unimpressive NOW, but the machine is 10 years old).
Only backdraw is, the power supply is large enough to sink an average-sized rowing boat. Good in the winter, not so good right now. Also, a pain in the arse when it has to be moved. I might get rid of it next time I move. I'll probably give it to a school that will use it for the next ten years, or something.