Lenovo Ideacentre B540 All-in-one - Black Screen

[mmartell]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

did the new drive have any smart errors?

SMART is never really too dependable. Sometimes drives will die without it even giving you an alarm. Sometimes it will alarm when nothing is wrong

Didn't test it for errors as it came right out of the packaging

Hmm. Are you saying there may be something wrong with the sata port ? Would that prevent the machine from booting ?

[WalterFarmer]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

if you are able to do a factory reset, or at least start it with the recovery button. Do these steps:

Note: Please back up all your data as running this reset will delete any data on your machine

1. Turn the machine off and press the recovery button which is located usually next to the power button. If you have a desktop machine you will need to power the machine back on and keep tapping the F2 key.
2. Use the arrow keys and press enter on system recovery. ( Desktop users can skip this)
3. Select “restore from the initial backup” and then “Next”.
4. Click “start” and accept the warning messages.

Length of time can vary depending on the speed of the machine.

Hope this will help you out.

[Uranium-235]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

did the new drive have any smart errors?

SMART is never really too dependable. Sometimes drives will die without it even giving you an alarm. Sometimes it will alarm when nothing is wrong

[mmartell]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

Yes I THINK it was. I was getting alot of SMART errors but how does one affect the other ? Strange to have two faults at the same time...

The data I copied from the old hard drive is actually in perfect health I was able to recover it (had to do with ownership) I think it was the boot sector (?) that finally gave in ie the data is fine but the drive is no longer bootable.

[Uranium-235]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

sounds like your old hdd might of had an issue?

[mmartell]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

Replaced the motherboard from eBay for $17 and all is well again. Well, except for trying to reinsert my /Home folder from Ubuntu 18.04 into a fresh install of 20.04. Seems to be incompatibility issues or maybe the home folder became corrupt.

[momaka]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

Hmmm. Caps in the PSU are good brand (at least the few shown in the picture), so maybe that's not the issue.

Did you check the thermal compound and heatsink contact on the CPU?
Also, try re-seating the CPU in the socket (provided it is not a soldered one.)

The more I think about the "Can't read location 0x________" errors you're getting, the more this suggests either HDD or RAM-related error (though that doesn't necessarily means the RAM is bad.) If it was the HDD, the PC should at least POST... though I know some OEM PCs take a very long time to do so if there is no HDD installed in the PC. So for that one, maybe try connecting a known good HDD to the PC (doesn't need to have an OS on it) so that BIOS doesn't possibly get hung on it in POST.

Otherwise, if the CPU is an i3... I think that's when Intel moved the memory controller from the NB to the CPU... so NB/chipset can't be the cause of the issues(?)

On the other hand, MCP/SB still is used as a bridge between CPU and SATA HDD ports, so perhaps the MCP/SB is dying? If nothing good seems to come out of this board, perhaps give the MCP/SB a quick reflow/re-heat and see if that does anything.

[Uranium-235]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

Chemi-con power supply caps ?

some chemi-cons are good.

[mmartell]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

Chemi-con power supply caps ?

[mmartell]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

The very first errors I saw were something to the effect of "Can't read location 0x5DFF0000". That was after choosing Ubuntu at the Grub screen and it attempting to load the OS. When I choose Windows 10 the OS loaded as expected. When coming back to the PC after several hours I found the kernel panic message.

Trying to reinstall Grub failed. Somewhere during this process the PC began to POST less and less during repeated power ons. I replaced the hard drive and managed to do a new Ubuntu install before the PC decided it wouldn't post anymore after restart, except rarely.

I thought the hard drive was bad and it probably was failing anyway. Ram tests good.

*Head scratch*

[piernov]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

BIOS can cause the machine to have a hard time to POST, but it wouldn't cause kernel panic. Maybe it's unrelated or maybe that's more of a PSU issue. If you have the equipment to look at the ripple you can try that, or hack in another ATX PSU.

[mmartell]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

Some pics

[mmartell]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

Tried another CMOS battery - no change.

I should have looked at the cap manufacturer but I didn't. The supply is turned on fine by the power switch and the 5v and 12v rails are coming up. If you're suggesting ripple could be the root cause, I can check for that.

I had the system boot once more but had no hdd plugged so got "No operating system detected".

Something screwy going on here. I'm not opposed to replacing the motherboard if I have to but need to be certain that's the problem before throwing money at it.

[momaka]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

I did not remove and open the PSU however I do measure both 12v and 5v rails when turned on.

That doesn't mean too much.
Does the PSU have known crap cap brands? If yes, I wouldn't rely just on a visual inspection.
Pictures would be nice too.

The things I thought were regulators on the motherboard are actually n-channel mosfets. One measures 1.6 ohm gate to source. Is that a red flag or is that normal for some of these on PC boards ?

For a MOSFET removed from circuit, any low resistance between any pins is bad. However, with the MOSFETs installed on the board, some of them can be across the CPU or GPU chip, which are often the source of such low resistances... hence the reading you see is most likely normal.

Moreover, failed MOSFETs typically don't let the computer even power On - you'll just get a twitch on the fans and a momentary "blip" of power before the PSU crowbars.

[mmartell]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

Popped open the PSU case, all caps pass a visual inspection.

The things I thought were regulators on the motherboard are actually n-channel mosfets. One measures 1.6 ohm gate to source. Is that a red flag or is that normal for some of these on PC boards ?

[mmartell]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

I did not remove and open the PSU however I do measure both 12v and 5v rails when turned on.

CMOS battery measures 3.15v. Will grab another and toss it in anyway.

Can't get into bios anymore.

Yes I removed the CD ROM, it has to come out for disassembly.

[momaka]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

Check PSU/caps, as already suggested.

Also check CMOS battery. Some OEM systems are picky when the CMOS battery gets weak or marginal.

If you can get into BIOS, try disabling "Show Full Screen Logo" or similar (should be an option to disable the OEM Logo and instead show a black screen with RAM and CPU info, along with BIOS enter key.)

When you say all peripherals removed, did you also remove the optical drive (if there is one)?

Last but not least, check thermal compound on the CPU. Maybe it's dry or heatsink is not making good contact. I did run into one Dell AIO PC a while back as a service tech, where the CPU heatsink stand-offs were soldered to the board, and two of them had broken off, leaving the heatsink crooked and letting the CPU overheat. The behaviour was the same more or less: first I could make the PC boot and work fine and even memory-test fine. But after a few days, it got progressively worse to the point where it wouldn't boot. Eventually the soldered i5 CPU gave up the ghosts. It was thermal-throttling when I was able to check it right before I could repair it.

The issue could also be due to a bad BIOS or failing CMOS chip. On that note, I do have an old dual-socket P3 motherboard that POSTs fine but then sort of crashes after POST. I suspect bad CMOS chip on that one. Hard to say, though.

[mmartell]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

Plugged a keyboard into one of the USB ports - no lights, no response when pressing Numlock or Caplock keys.

[mmartell]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

I've removed all peripherals as well, makes no difference.

When I get home I'm going to check power supply voltages and regulators top side of board.

Seems like either the processor isn't running or bios is corrupt maybe ? Notwithstanding the giant thread here asking for bios bins how hard is it in fact for the bios to become corrupted ?

[mmartell]

Re: Lenovo Ideacentre B540 All-in-one - Black Screen

i3 six gb ram