i would go with ubuntu, specs are too low for anything higher than windows 7. if you manage to get at least 2 more Gigs of RAM (assuming you have the 2GB model) you could try windows 8.1 but the cpu worries me to be honest and Ubuntu is better than evern right now. Good Luck

it does not happen always but the antenna could have gone out of place, if you feel comfortable opening electronics this phone is not hard at all, go check a tear down video and look for the antenna cable, and make sure both ends are in place if the phone does not have a cable then it has to be a contact type antenna

if you are trying to get to DFU to do a restore (this will delete all your data on the phone, not icloud) 1.connect to phone to the pc and open itunes 2.hold Power + Home button for 10 seconds 3.Release Power button but keep holding Home button for 5 seconds or until you hear the pc sound when you connect a device ( if you see the apple logo, you holded home + power too long, repeat step 2) at this point itunes should detect the phone in DFU and should let you do a restore, this will trigger icloud protection if there is any, make sure you know your password to the icloud account or you wont be able to access your phone. Good luck!

unfortunately that laptop model has the cpu soldered but what kind of work you do on the laptop? is not bad at all for most people, best thing you can do to get a quick boost in overall system speed is, if you have a mechanical hard drive, replace it with a SSD specially with prices of those today are way cheap that a few years ago and trust me mechanical from SSD is like night and day. check how many GB of system RAM has, is really easy to get at least 8GB of RAM with those 2 things you should feel the laptop like brand new if you are rendering of playing high demanding games then you should start looking more in GPUs but then again most are soldered, if you have the 2018 model you should be able to use external GPUs via Type-C connector. hope this helps

happened to me when i upgraded from 8.1 to 10, all i did was uninstall the old drivers completely and then reinstall the new ones and during installation of he drivers the keyboard backlight started to work again, good luck

most likely liquid damage

did you enable developer options by any chance? there are a few test options in there that probably got enable Update (03/02/2019): ok, when you have the phone go to the settings and look for Developer options is almost always above About device, once in developer options scroll and look for Show CPU usage, if its On then that is your problem, turn it off. if you don not see developer options its ok, go to about device scroll and look for Build number, depending on the android version in could be inside another menu or in the main menu of about device, if you don not see it on the main menu of about device, look for anything named software and tap it. once you see build number tap it a few times, you will see a count down keep taping it after the count down runs out and you will see a message saying “You are now a developer”. now back out to the main screen of the phone settings and now above about device you should see developer options, follow the first steps to find show CPU usage. Hope this helps! if...

if the battery cover is original it will have the imei at the bottom, hard to see i suggest some kind of led light to shine against it

could be a dozen reasons but i wild guess, they had one with something bad (earpiece, loud speaker bad etc etc.) and then they saw yours and replace the bad part with yours? either way is messed up ppl steal phones

Jailbroken iphones are sometimes a timebomb specially if you have lots of tweaks. If you tried the home and power button to restart it and its doing the same, you will have to put the phone in DFU mode and restore it with itunes, sometimes doing a restore with a jailbroken iphone give errors Keep in mind that restoring the phone will lose jailbreak. If you have the shsh of previous versions you can do a custom firmware and restore that to keep jailbreak Good luck!