Dell T7910 Refuses to post even after replacing every component.

Question

Hello everyone, I recently picked up a dell T7910 and upon trying to turn it on everything spins to life, the power light is a solid white, I get a green flashing on the raid controller and the CPU heats up slightly but other than that it is completely stuck during post. I never get anything out of the 1050 ti connected to it or any lights on a keyboard. I've been following others posts to try to figure it out and dove down the rabbit hole on a few which is where it starts to get interesting. First I read it could be an issue with the ram, so I got two new ram sticks, still has the same problem. Second I read it might be a bad motherboard, So I got two new ones just in case that was the issue, Neither fixed it. Third I thought I might just have had bad luck and none of the motherboards BIOS were compatible with the CPUs I had so I got a couple more including one E5-1620 v3, but sadly same issue. Fourth I threw a new PSU at it in case that was the issue and it still wont post. I've tried other troubleshooting steps as well not just shooting the parts cannon at it but none turned up anything useful. If anyone could answer my prayers and get this thing working I would be very grateful as I have enough parts for 2-3 of them by now.

bradthetechnut · Answer

If not already, start by testing or replacing the size 2032 CMOS battery. Even if the extra MB's came with batteries, sellers never make sure they're any good.

A bad battery affects BIOS and therefore PC operation.

user_f63187 · Answer

@bradthetechnut​ I just ordered some more to test with, I checked them though and they all read above 3v. Would a bad CMOS really hang the bios like that? I've never experienced that on any other platform.

bradthetechnut · Answer

Not every component was replaced.  The GTX 1050Ti is getting a little old, and sometimes they fail, though not often.  I doubt it's the RAID card since you get a green light,  but it would be next.

user_f63187 · Answer

@bradthetechnut​ 1050ti is my testing card and I verified its function on a different computer about 3 times during testing. Raid controller is built into the Motherboards so it's been replaced twice too. Every component has been replaced except the power connector wires but those trace out fine. I even swapped it into a different case in case that was the issue.

bradthetechnut · Answer

'Would a bad CMOS really hang the bios like that?'  Yes.  When I had a bad battery in my Precision 3620 and tried ignoring it for a while, at first it would freeze a few times.  Then it went BSOD and it's recovery options didn't work.  Then I unnecessarily tried reloading Win10.  That wouldn't work either.  So I replaced the battery and reset BIOS.  Then I had to finish reloading since I already started it. Try resetting BIOS via the blue jumper method. Time to do a fresh install.  You never said if boot drives were replaced or not or their status.  Replacing and starting totally fresh isn't a bad idea. Download Win11 from the Microsoft site.  Use an 8GB or larger flash drive formatted to FAT32.  They often come that way anyway.  Your PC is from 2014 and isn't on the supported list for Win11.  Microsoft site Win10  Microsoft site download Win10 ISO (recommended) You'll probably need to inject a driver upon reload.  @Chino de Oro knows what driver that is or how to find it. Lastly, one idea is to put all the original components back and return the thing.  I hope the 7910 came with something for a return policy.

bradthetechnut · Answer

For loading or reloading OS, BIOS should be set to AHCI or RAID and Secure Boot On.

user_f63187 · Answer

@bradthetechnut​ New Cmos arrived, has not helped on any of the motherboards. Bios reset via jumper has been tested quite a few times but I just did again with no change. There is no boot drive installed when I do these tests other than when I installed a known working windows instillation and I also tried an ubuntu server pre setup on another machine to open a ssh server. Ssh server never opens. OS shouldn't matter though as it never even gets to initialize HIDs let alone Pcie busses or BIOS. No return policy sadly or I would've thrown in the towel long ago. Now I can't even be comfortable parting it out because I can't tell what's wrong with it. Physically there should be no issues but still doesn't post which is what's making me scratch my head.

bradthetechnut · Answer

So you can't even load/reload OS?  what driver needs to be injected into flash drive for loading operating system on a Precision t7910

user_f63187 · Answer

@bradthetechnut​ No sadly this is not an issue on the OS level this is rather a hardware/ Post and bios level. There is either something going wrong in the power on self test or something going wrong In the bios that stops the boot from continuing. No drives are initialized, Usb never begins communicating and neither do the PCIE lanes. It never gets into the bios or I would be able to see life on the keyboard like caps lock or an output from the gpu. Unless dells are different from every other platform i've ever worked on. Thank you again for the help.

Precision Fixed Workstations

Dell T7910 Refuses to post even after replacing every component.

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