PC Won't boot

Haole Boy

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Aloha everyone. Customer brought me a Dell Inspiron 7790 AIO that will not boot. He's looking for an estimate to send to Dell for warranty coverage (not sure why Dell isn't fixing this, but whatever, I need the business).

When you power on, you just get the 'spinning dots' for several minutes, and then it hangs (dots stop spinning). A couple times I got to the Preparing Automatic Repair screen, but it again just has spinning dots for a long time, then a Blue Screen with DRIVER_PNP_WATCHDOG

Tried booting a Win 10 20H2 install USB made using the Microsoft media creation tool. Same thing, but eventually gave me a DPC_WATCHDOG_VIOLATION error.

I don't see any way to resolve either of these blue screens on a system that won't boot.

My usual first step is to boot from Gandalf's WinPE and create a full disk image, but it won't boot from the USB either. I hit F12, select the USB drive, and I get the Loading Files screen with a progress bar. Once the progress bar gets to the right hand side, then it goes directly back to the Dell logo and the spinning dots. With a Linux Mint USB stick, I get to the GRUB menu, but when I hit enter to select the Mint system, back to the Dell logo and spinning dots

BIOS shows two drives:
- Seagate Barracuda ST1000LM049
- SK Hynix BC511 NVMe 512GB

Any suggestions on how to get this thing to boot from an external USB drive? I've been through the BIOS settings, and I don't see anything obvious that would prevent the system from booting from a USB stick. The system does have BitLocker turned on, could this be part of the problem?

Also, there are three updates available for the BIOS, and it appears that BIOS can be updated through F12 - Other options. But when looking at the Dell website, they tell you to disable BitLocker first. No way to do that without booting that I know of. So, I'm kinda stuck.

Mahalo for your assistance!

Harry Z
 
The device almost certainly has a hardware problem to not boot from any source, and updating the BIOS is not a great idea unless any hardware problems are sorted first.

Usually, I would suggest removing everything plugged in, all expansion cards, disconnect all drives etc. and ensure it is POSTing fully. The dots may be from the boot loader of the OS or UEFI; I am honestly not sure, but my first thing would be to disconnect the hard disk drive and do a full BIOS reset to factory. Dell has some built-in diagnostics on most laptops... it has been so many years since I have troubleshooted one, I cannot remember the sequence, but do an Internet search and you will find it. Run all the quick tests for the hardware, motherboard, cache, etc. and run their Memory Test. Another option is to run a test like MemTest86+. You should probably set the bios back to MBR or Legacy before you try to run the test. If there is bad memory find out if there are sticks or if the memory is soldered on the motherboard. Obviously, if it is soldered and there is more than one stick isolate the problem to a stick and furthermore rule out it being the slot vs the stick. It is also good to remove the main battery and unplug it and press the power button.

At this point address any failed hardware and if nothing pans out just call it as a motherboard. CPUs rarely go bad such as less than 1 in 1000., so that is really not it.

If everything starts working, re-connect the hard drive and set it to UEFI if needed. If the problem recurrs, run some drive diagnostics because the symptoms here are that of a bad hard drive in a LOT of ways though I would have expected it to at least boot sometthing else like from USB. That said, I could see the BIOS waiting on a drive to spin up or encountering read delays and spinning something while it is stuck detecting. Again, I would have to know if that is part of Windows or the BIOS, your boot order etc. It is pretty common to boot something like from a memory stick and the unit still has to detect the attached drives.

It is just the process of elimination and guess and check mostly. That said, this is almost certainly a hardware issue. Most likely the drive or motherboard. Still need to go through figuring it out for certain, resetting things to factory, etc. to rule everything out.
 
He's looking for an estimate to send to Dell for warranty coverage (not sure why Dell isn't fixing this, but whatever, I need the business).

That's a big red flag.

With a problem like this you'll probably only know how long it'll take to fix it after you've fixed it - it's a bit late to quote for the work then.

If it's under warranty then it's Dell's problem - run away! If it's not, then get the client to sign a bit of paper saying that he accepts full responsibility for any data loss during the diagnosis (Bitlocker is like that) and make sure you have an up-front payment to cover your likely diagnosis time - at least an hour for something like this.

Paranoid? Maybe, but this sounds like a deep hardware problem (the Mint failure points to that) and I'd hate to see you on the hook for losing the client's data just because you were the last one who "fiddled with it".
 
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@Haole Boy isn't on the Continent so round trip shipping would be expensive. As in probably $200+. What I'd be interested in is if Dell is going to provide the parts as part of the process.

It does sound like a hardware problem. My first steps would be to remove the OEM drives then try booting with an external source. Go from there.
 
Aloha everyone. Customer brought me a Dell Inspiron 7790 AIO that will not boot. He's looking for an estimate to send to Dell for warranty coverage (not sure why Dell isn't fixing this, but whatever, I need the business).

When you power on, you just get the 'spinning dots' for several minutes, and then it hangs (dots stop spinning). A couple times I got to the Preparing Automatic Repair screen, but it again just has spinning dots for a long time, then a Blue Screen with DRIVER_PNP_WATCHDOG

Tried booting a Win 10 20H2 install USB made using the Microsoft media creation tool. Same thing, but eventually gave me a DPC_WATCHDOG_VIOLATION error.

I don't see any way to resolve either of these blue screens on a system that won't boot.

My usual first step is to boot from Gandalf's WinPE and create a full disk image, but it won't boot from the USB either. I hit F12, select the USB drive, and I get the Loading Files screen with a progress bar. Once the progress bar gets to the right hand side, then it goes directly back to the Dell logo and the spinning dots. With a Linux Mint USB stick, I get to the GRUB menu, but when I hit enter to select the Mint system, back to the Dell logo and spinning dots

BIOS shows two drives:
- Seagate Barracuda ST1000LM049
- SK Hynix BC511 NVMe 512GB

Any suggestions on how to get this thing to boot from an external USB drive? I've been through the BIOS settings, and I don't see anything obvious that would prevent the system from booting from a USB stick. The system does have BitLocker turned on, could this be part of the problem?

Also, there are three updates available for the BIOS, and it appears that BIOS can be updated through F12 - Other options. But when looking at the Dell website, they tell you to disable BitLocker first. No way to do that without booting that I know of. So, I'm kinda stuck.

Mahalo for your assistance!

Harry Z
Seems to be related to the SATA devices but it's either firmware configuration or motherboard failure or device failure. My things to try are:
1. Reset BIOS to factory defaults.
2. Look for bios settings related to sata/ahci and try the different settings.
3. Disconnect all sata devices, reset bios.
 
If the machine is set for UEFI Secure Boot, doesn't it have to be able to detect and read the EFI files on the hard drive? (Correct me if that's wrong.) If those files aren't available (because the drive is not detected at all, or because its health is such that the EFI partition isn't readable), then it can't boot anything, aiui.

Can you get into the BIOS to change to Legacy (which should unlock the USB/optical booting of rescue stuff)?
 
Does it have the NVMe running in RAID set in the BIOS. I've had two failures like yours recently. One I discussed here in the forums. I ended up giving up and never resolved it. Set the BIOS to AHCI mode and turned it into a Linux bench machine as the customer had lost all confidence in it after three failures.
 
That's a big red flag.

With a problem like this you'll probably only know how long it'll take to fix it after you've fixed it - it's a bit late to quote for the work then.

If it's under warranty then it's Dell's problem - run away! If it's not, then get the client to sign a bit of paper saying that he accepts full responsibility for any data loss during the diagnosis (Bitlocker is like that) and make sure you have an up-front payment to cover your likely diagnosis time - at least an hour for something like this.

Paranoid? Maybe, but this sounds like a deep hardware problem (the Mint failure points to that) and I'd hate to see you on the hook for losing the client's data just because you were the last one who "fiddled with it".

Talked with the customer some more about the warranty situation. The Dell warranty has expired, and he's looking for coverage under the Costco 2nd year warranty. This appears to be a reimbursement for the cost of repair, so I will take the advice given above and disconnect the internal drives and see if I can boot from one of my USB sticks.

Mahalo,

Harry Z
 
Talked with the customer some more about the warranty situation. The Dell warranty has expired, and he's looking for coverage under the Costco 2nd year warranty. This appears to be a reimbursement for the cost of repair, so I will take the advice given above and disconnect the internal drives and see if I can boot from one of my USB sticks.

Mahalo,

Harry Z

Need to keep one thing in mind. It's not a repair at any cost. The underwriter will determine whether it's more economical to repair or buy out, as in replace/pay residual value. And you'll need to have your own warranty clearly stated.
 
Made a little bit of progress, maybe...

I removed both hard drives, still can't boot my Gandalf's WinPE USB stick. Get the "loading files" and when that ends, the Dell logo reappears and the spinning dots show up, and then stop moving a short time later. Waited several minutes, nothing changed

System has two 8 GB RAM modules, pulled one out and tried again, same thing. Swapped in the one I removed, same problem.

Reset BIOS to "factory defaults', Gandalf's WinPE now gets to the initial desktop where is says 'System Configuration', and seems to hang there (no spinning dots or any other indication that there is activity)

Put the drives back in. Now boots to "Preparing Automatic Repair" with spinning dots and eventually hangs there after several minutes.

So..... motherboard is bad?

If so, where would I find one to get a price for the estimate? Looking at the motherboard it is clearly marked IPCML-CL Rev A00, but searching for a replacement only gets me this one on ebay, but they don't ship to Hawaii. What source do you use for Dell motherboards?

Is there another part number someplace on the motherboard I should be looking for. I'm attaching the parts list from the Dell website, and I don't see anything that looks like motherboard on this list, but maybe someone else can find this.

Mahalo for all your assistance,

Harry Z
 

Attachments

  • Inspiron 7790 parts.zip
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Have you checked the HDD/SSD etc for any issues?

Can't really do much with them as they are encrypted with BitLocker. I was able to get SMART data for the HD, no errors indicated there (and, yes, I do know that a "clean" SMART report is not a 100% reliable indicator of a good drive). Can't do anything with the NVMe drive as I don't have an enclosure to put it in.

Mahalo,

Harry Z
 
Sounds like the motherboard if you can't get it to boot with the other drives unplugged. Dell's gotten to be a pain in the .... in the last few years. Used to be easy to pick the MB part number. There should be one on the existing model. Based on the picture I found below it should be by the CR2032.

GUID-BB53536E-CCE2-4A6F-8C55-9C35A02615AC-low.jpg
Dell will probably sell you a new one as well. I'd give them a call first to check on that.
 
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I found below it should be by the CR2032

The first time I read this, I thought you were telling me the part number is CR2032! 😂

Mahalo to everyone who replied. I don't have an NVMe drive to try an install on, so I removed the NVMe drive and the HDD, installed a spare HDD and tried to install Win10 from a USB stick. System booted to a blue screen (nothing on it, just a blue background) and then turned itself off.

I'll be calling Dell to price a replacement motherboard.

Harry Z
 
Just quickly though had you tried to reset the CMOS and remove RAM Modules for a few minutes, then reinsert. Or judging by that board diagram JMP1 looks like the CMOS Jumper - remove that - reallocate to middle pin - wait a few seconds then reinsert into original location (refer to link below)

as @glennd stated - try another drive. As it may just be a bad update/driver/Bad Drive that has caused this issue. I have had it once before - cant recall what I actually did though - think it was CMOS clear. It was not the MOBO though.

CMOS Jumper Reset
Service Manual
 
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