workstation stopped to boot

galk,

If you have a Supermicro Superworkstation, I would be surprised if it were a motherboard, or power supply problem. Those are server-like in their build quality and reliability. The problem in order of probability seems more likely to be: memory failure, thermal, CPU or BIOS problem.

1. Thermal: Check that all case, CPU, and memory fans are running.

2. Memory: The system will not start without memory. Try starting on only one RAM module and ensure it is installed Slot 1 / CPU1 of the Supermicro X9DR7-lN4F . See:
ftp://ftp.supermicro.com/CDR-X9_1.30_for_Intel_X9_platform/MANUALS/X9DR7_E-LN4F.pdf > Page 2-11

The tests will be complicated by the presence of dual CPU's. As there are two CPU's installed you may be required to have at least RAM one module for each CPU, so is the first test has no results, add another module in the first slot related to CPU2.

3. CPU: The E5-2680 has a MTBF of 170,000 hours- continuous running oro 19+ years but one of them may be getting too hot. After cycling through a reasonable number of RAM combinations, remove both CPU's- typically you will need a long-shank screwdriver, and remount each CPU in turn in CPU 1 position. If you haven't done this previously, see YouTube videos. With LGA2011 as it is such a large die, I clean both the CPU and heatsink surface with denatured alcohol, polish the heatsink surface with a block and scouring powder, making certain when done that all traces of powder and alcohol are gone. Make a very thin diagonal bead in an X-shape on both surfaces and then spread the thermal paste (Arctic Silver) with a business card over both surfaces. the coating should be as thin as possible so that the surfaces are just covered. Screw the fan /heatsink down in small steps in a diagonal pattern- a bit like doing up a car wheel and don't really crank down on it.

This is a bit of fuss and needs care, but is is an important skill to know and importantly will eliminate a possible marginal installation o the E5-2680's.

4. BIOS The problem has BIOS implications, it seems unlikely, given the sequences done already and as it's the BIOS that is running the fans full bore.

Let us know what you find out.

Cheers,

BambiBoom

CAD / 3D Modeling / Graphic Design:

HP z420 (2015) > Xeon E5-1660 v2 (6-core @ 3.7 / 4.0GHz) / 32GB DDR3 -1866 ECC RAM / Quadro K4200 (4GB) / Samsung SM951 M.2 256GB AHCI + Intel 730 480GB (9SSDSC2BP480G4R5) + Western Digital Black WD1003FZEX 1TB> M-Audio 192 sound card > 600W PSU> > Windows 7 Professional 64-bit > Logitech z2300 speakers > 2X Dell Ultrasharp U2715H (2560 X 1440)
[ Passmark Rating = 5581 > CPU= 14046 / 2D= 838 / 3D= 4694 / Mem= 2777 / Disk= 11559] [6.12.16]

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[ Passmark System Rating= 5322 / CPU= 19675 / 2D= 767 / 3D = 3544/ Mem =2337 / Disk = 12951 ] 8.15.16

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