Z620 Won't POST (4 beeps - Power Supply Failure) With 2nd CPU Riser Fitted - Otherwise Runs Fine

[watmough]

I recently purchased a used Z620 configured with the 2nd CPU riser, dual E5-2690, 32 Gbytes on each CPU for 64 GBytes total. 2011 Boot Block

The computer has been running great, but then I came back (was only out of my home office for a few minutes) to find a red power button and 4 beeps. PSU failure, according to the docs.

I did not smell any smoke and there are no visible burn/scorches I can detect.

 I was able to get it up and running again by removing the 2nd CPU riser. With the riser out, it boots and runs fine. Zero issues apparent.

I have tried the following troubleshooting to get the computer to work with both processors:

* Vacuumed the dust off the riser,

* Reseated the memory

* Tried with no memory on the riser

* With fans disconnected and riser out, I get normal bios error messages

However, if the riser is in, the computer fails consistently with red power button and 4 beeps.

What are the best next steps for troubleshooting, and I have some ideas as I have a Z620 upgraded to Ivy Bridge (dual E5-2637v2 32 GBytes total) at work:

* Try my (failing?) PSU in my work computer,

* Try my (failing?) riser in my work computer (will E5-2637v2 vs E5-2690 be ok? Any risk to my work box from the riser?)

* Anything else to try with the riser?

* Any one have any thoughts on whether the PSU getting marginal or riser would be the more common failure?

* I already ordered a used PSU from eBay, basically on hope that it really is just the PSU getting tired.

[watmough]

Update: PSU is fine. Tested out ok in another dual-cpu Z620.

Processor issue? Motherboard? Riser?

Next troubleshooting steps?

[watmough]

Troubleshooting contd:

I swapped the CPUs, and the riser cpu runs good on the mainboard.

It was klarted with thermal compound with just a few specks actually making it *under* the cpu, so I will try cleaning up the riser also. 

Question: can you put an empty riser in the computer? Will it stop it booting? Should you get a processor missing error?

[sadpandas]

Just wondering if this was resolved?  

[watmough]

Sadly no!

The machine works without the riser, but I suspect that a power brownout did a number on the motherboard. I even tried with a known-good riser, still no dice.

[DGroves]

swap the cpu/ram between the riser card and the motherboard one at a time.

this will remove them as points of failure.

if the system rums after the swaps, the issue is most likely something on the riser card or motherboard riser socket

check the motherboard/riser for bulging caps also inspect where the riser mates to the motherboard, and trace the power supply lines if possible

swap the power supply,

if all of the above fails to resolve, then the motherboard may be the failure point

[watmough]

Thanks!

I already tried with minimal RAM, checked the riser socket, checked with anoth riser, changed PSU, swapped the CPUs even.

Pretty sure something on the motherboard got fried. All 32 threads were running one minute, then when I came back to office, it was just making some sad bleeps.

Without the riser, it has been running fine since I posted this thread.

If anyone has a spare z620 motherboard, I would be very happy to PayPal the postage ... Or could trade for a riser (no cpu/mem but with shroud and cooler)

[sadpandas]

Thanks for the update and tips!

[watmough]

I'm really sad now ... my original Z620, which is a very early block 2, and upgraded to dual E5-2637s ... also just failed. I though pulling the daughterboard might help, and it ran for a few hours (enough to pull some files off) but now just red led of death.

I will try a PSU in it, but not holding out much hope.

I guess 5+ years of solid service is pretty good!

[sadpandas]

I confirmed mine was a dead system board ;(  Confirmed with other z620's on site.   Im sad as well! It was my first pci 3 bus...first SSD install.  RIP! Stevie Hyper HP!