to do a PC HARD POWER RESET
Is your PC dead?
BIOS screens dead too? Monitor shows NO SIGNAL or the like?
The are many ways for PC to lock up this cures about 5 causes.
I also show how to this reset for servicing the PC hands on inside.
I will do this page in 2 parts, one is for PC is dead (how to do simple hard power reset, and how to do service on a PC, and not blow parts to H3LL.
The PC called a Laptop remove the big battery and test with no big battery there on AC power Pack only. (if a battery shorts the PC will be dead)
If the PC is Deaktop there is no huge battery there, but all PCs have RTC coin cell battery that if dead , BIOS screens can go dead, and the PC.
If the RTC coin cell battery is dead, replace it below 2.9vdc. (it costs only $1 to replace it, and only lasts for 5 to 7 years) On any desktop this is childs play on Laptops , from easy to pure hell is possible on laptops.(RTM?)
If you like videos, on this see this one here. (shorting the battery socket battery out is useless, it has diode block there to prevvent south bridge damage, yes intel is smarter than noobs !)
This is just the steps for for a hard reset, not doing service on the PC, covered in the next frame.
This is not hard at all, and resets all ESD and latchup events, even stuck in sleep mode events. (the latter is bad software drivers in the PC's OS)
If a laptop that huge battery in the PC must come out first, some are easy , just drop off bottom and some thin notebooks pure hell to reach. (on a real desktop this is just 4 steps, and is really childs play simple)
If this fails make step 3 , 1 full hour long. (even over night in very extreme cases)
Servicing any PC and not wanting to blow up expensive modules inside any PC.? (work safe don't blow up $300 components, ok?)
Rule #1 on all PC's is never remove and HOT swap parts inside ever !, that means with the AC line cord to the wall AC jack, at anytime, if you do this wrong you will blow up the part and /or the MOBO. BOOM !
Do step 1 to 3 above then... (on a laptop of any kind the big battery was remove long ago above)
The hard reset cures that cause of failures. (some are only temporary , and stated last in the list.)
What is CMOS latchup (a Parasite)?
What is chip input protection latchup (on purpose)? (answer is vast but a simple diode pair or zener diode pair or TVS device works) there are smart active protections too,, that assume one hit will follow with many more and stronger)
What is ESD latchup and protections ?, see line 2 above. (some can protect pins up to 25,000volt spikes of ESD events. (even minor lightning hits)
See smart protections here. (first is SCR protecting see the low hold-in words and how the above reset methods release this SCR device)
The thing to learn here is that those clamps can hold in until all power rails go to very near zero 0volts. or below 0.3vdc.
version 4. 12-9-2017 (revised 1 -1-2020) I split the page so folks don't get confused. (latch up and service mode)