Panaceyya,

I am certain this is going to be based in the OS, and not the hardware. You can download and use this diagnostic to test the hardware outside of the OS to be sure. I would also suggest you make sure the server is up to date on BIOS, BMC, Raid controller, and drives. It is most likely that a service or system process, within the OS, is whats causing it, which we wouldn't be able to assist with. So start with updating the server and testing the hardware with the diagnostic and let me know what you see.

Due to a page issue I can't embed the link I discussed for the diagnostic tool, so I am giving the link here - https://dell.to/2JLpgHD

I have latest drivers and installed Dell Support Assist & Dell Diagnostics.

Opened online page with Dell Diagnostics, started test and it goes around hour on first step like "Gathering test", tryed to reboot and go again - still the same

OS - Windows 10

Yes im booting 32bit version from link which you sent me and its hanging.

Also i Started Dell SupportAssist on PC and it can scan all but not Hardware Scan, it says like "Error occuried for this request"

I have windows 10 64bit.

So you are booting to the 32bit diagnostic  media you created, and it is hanging? Is that correct?

Any ideas what it can be ?

Try powering off the server, remove the powr cables, then hold the power button for 20 seconds, After that open the case and locate the NVRam jumper on the motherboard and move it over, and power up to clear the NVram, restore the jumper and then boot back to the diagnostic, any change?

32bit diagnostics, to test the server outside the OS. 

Thank you for answer. But what you mean about "boot diagnostics" . You mean boot diagnostics before OS Loads or you mean Dell Diagnostics on OS Load ?

all test are passed, everything is OK.