Constantly Rebooting every few mins

Question

Hey, my device is constantly rebooting every few mins.
I bought it from ebay classed as 'spares or repairs', and the post stated that it was not receiving signal and stays on "searching...". no big deal as i only wanted it for a cheap ipod for my younger brother.
is there any way i can stop it from doing this rebooting thingy? i've tried the method of turning on 3g then restarting the phone then inputting a sim but that hasn't fixed it :/
any and all help is much appericated

Answer 1

This kind of crash is usually or always caused by a memory fault. If you've upgraded the memory modules, reinstall the original ones and see whether there's an improvement.
Apple Diagnostics or the Apple Hardware Test, though generally unreliable, will sometimes detect a fault. A negative test can't be depended on. Run the extended version of the test, if applicable.
You can try reinstalling the OS, but most likely there will be no change.
Otherwise, make a "Genius" appointment at an Apple Store, or go to another authorized service provider to have the machine tested. You may have to leave it there for several days. There isn't much point in doing this unless you can reproduce the crash, or if you can't, it happens often enough that it's likely to be repeated at the store. Otherwise you may be told that nothing is wrong.