Z620 does not start, on the POST card is constantly lit RESET

[Vadim_69]

Z620 does not start, on the post card is constantly lit reset. After 1 minute, the CPU fan is accelerated.

[Hiatus]

Did you change any settings or hardware before the problem appeared?

Can you reach the BIOS?

If you can get in to the BIOS, try factory settings. If not, try reset CMOS.

Hiatus

[SDH]

My guess, from symptoms:

OP tried to update BIOS from within OS10, and corrupted BIOS.  Hence, time for OP to search for the Crisis Recovery Jumper post in here, and to hope for the best......

[Vadim_69]

Yes, I wanted to turn off 1394. Maybe I did something wrong. How to return to default settings? There is a button near the battery: signed by CMOC.

[SDH]

It is hopeful that you did not do a BIOS update to get to this bad point.  Maybe it will not need the Crisis Recovery Jumper method to recover from.  However, corrupted BIOS does not only happen from a bad BIOS flash event.  You want to try to get back to factory BIOS settings if you can. 

Can you get into BIOS at all?  If yes, then go to the first tab along the top and drag down to the option of factory settings (or some such term).  Choose yes and then you need to save those changes on the way out of BIOS.

Or, if you can't get into BIOS the normal way you still may be able to clear this up by taking away all power that might be keeping a mildly corrupted BIOS from being cleared.  Remover the power cord.  Disconnect all peripherals such as mouse/keyboard/monitor cables from the backplane, and also the ethernet cable.  Remover the motherboard battery.  Press the start button.  Hold your slightly moist fingertips crossing all three prongs of the power supply cord attachment.  Press the little spring loaded CMOS reset button you found on the motherboard and hold 5 seconds.  Wait an hour, do all that again.  Put back in the battery.  Press the CMOS button again and hold in for 5 seconds.  Reattach all your peripherals except network cable.  Reattach the main power cable.  Turn on the workstation.  This may work, but if it does not you likely have a firmly corrupted BIOS that can be recovered only by good luck and use of the post I've referred to above, here on the forum.

All those steps above are to fully drain capacitors and remeove as many electrons from the motherboard so that when you clear the corrupted CMOS by pushing the little button the chances of the bad BIOS over-riding the factory settings is kept to a minimum.  The factory settings are in firmware, but they too can get corrupted.  In that case you need to reload BIOS from a known-good source via the crisis recovery method.

[SDH]

If you can get into BIOS and navigate down to the Factory Defaults section of the first "tab" it can be a bit confusing what exactly to do.  Here are the steps from the Z620 manual, and follow these strictly in exactly this order to end up with the factory default settings:

To reset to factory settings, select File > Default Setup > Restore Factory Settings as
Default. Press Enter to accept the changes, and then select Apply Defaults and Exit. This
restores the original factory system defaults.

The actual BIOS wording might be slightly different from what is in the manual......