Ifyou have a cheaper laptop, the extra insurance is probably not worth the expense. Try a known good AC Adapter, is same thing happened, mobo and dc in port need to be replaced. 1. removed the Battery and AC Adapter then press the power button for about 20 seconds and try to boot the system. 2. Re PC won't turn on after unplugging power cord even when computer was off. I suggest you need to get a higher wattage PSU. The 5850 requires and minimum of 500w to run then you need to take into account the cpu,motherboard,ram,hard drive, opticle drive, fans etc etc The cpu alone will use 75w along with the motherboard. I suggest looking at a better make of psu too such as the corsair 650TX Step3: The Quick Fix That Lasts. I suggest sewing machine oil if you can find it, but most lubricants (NOT WD40 - that's not meant as a long term lubricant) will work. Motor oil is a bit thick for our needs, so only try that as a last resort. First, let's see if your power supply qualifies for this fix. Looking at the back of the power supply Checkall internal connections inside your PC, especially power connectors to peripherals. Remove all peripherals and hardware from your computer except your boot drive and graphics card if you Whenyou press the power button to turn on the computer but there is no display on the monitor, please follow the below steps to troubleshoot : 1. Check the power supply. 2. Check the CPU. 3. Check the memory 4-pin EATX12V_2 and 24-pin EATXPWR, we suggest to connect all three connectors to the power supply. (Model name of photo below is ODEHE.

computer not turning on power supply ok