remove the mxm card. will force it to use the integrated. something might of forced current through the monitor into the gpu, or the gpu could of melted its solder balls as that is a piss ant cooler for a desktop CPU and MXM gpu..

There's a buzzer label next to the vertical crystal. Also, test the ram modules on other machines and check the voltage on the CPU VRM. Optical drive seeking and the fan working doesn't mean a working processor or a booting machine, because the power button and fan control are handled by the LPC bridge chip. The optical drive seek is made by itself when power applies to it so doesn't need the sata connector.

UMI input wont work as long as there is a dedicated graphic card connected. Also check for bad memory sticks. If all else fails, go back to basic. Disconnect anything non-essential, keep only power, ram and the monitor connected basically.

Typical fail point on these machines is the GPU. The onboard card voltage regulation tends to fail if the machine is subjected to an overheat issue.

I get these machines all the time and they suffer greatly with heat and im 99.9999999% Its Killed the Graphics card but i believe ive have had 1 or 2 before with faulty Ram/slot. The Backlight is logic controlled and when it passes all hardware tests it then initializes the backlight and LCD, with the card being dead it wont pass and thefore wont turn on backlight. If you wish to use the onboard graphics you MUST remove the MXM card and not just swap headers as bios detects the card in the slot and disables the onboard.

If you suspect a dead back-light you can always try shining a bright torch on the screen

It is an HP. Put it back in the trash where it belongs.

9:00 - I love how you tell us it’s booting into windows.. right after you tell us the hard drive has been ripped out 😛

Take the MXM graphics board out and then try the integrated graphics.

the center pin is for Dallas 1-wire communications in laptops that support it-- some cheaper HPs don't care. the GPU probably failed. remove the GPU MXM card and try the internal video.

The little odd-man-out USB port is for the wireless keyboard/mouse receiver. It tucks in the back there under a panel so it's easily swappable but not hanging out where someone can snap it off accidentally.

Dave, Remove the MXM GPU Card and plug the monitor in to the built in port, the BIOS will always default to the added GPU if detected and present, it may be that the card is seen but not functioning correctly. Also you can verify if the computer is reaching any kind of on state by plugging in a USB Keyboard and checking the numlock.

Hey Dave, it is possible that the PC is not fully booting due to the PSU not identifying itself (it is the purpose of the single wire bus that goes in the center pin of the DC jack). HP and other manufacturers use this approach with their PC's (especially laptops) to make sure the right PSU is being used with the device.

It's about time you get some crap from the dumpster like the rest of us... :)

The word "attempt" is missing from the video title. I feel like I wasted half an hour..

pull the mxm card

"Im sure its booting into window" It cant, the hard drives gone

GPU dead. That's common on these machines. I had one with a GeForce Go internal card and it died. The thermal management for these can be lacking under high loads. I checked the price for these replacements even used pulls, and it's cheaper to buy a new machine than to replace it. It would be better since you got it free. Thanks for showing us how to troubleshoot this!

I fixed the same model by flashing the BIOS rom on the EEPROM chip on the motherboard with a BusPirate, should work here too. Could be some easier way, but that's how I did it.

remove the MXM gpu and switch to UMA LVDS it should work if the external gpu is toast

It may well be that the bios is corrupted as some have commented. Last year, I found a Dell 27" i7-3770S AIO touchscreen 16GB without the hard drive but with a spare motherboard and a spare power supply. On the net, I found that people were complaining about the bios. So the first thing I did, was to find a bios for it. Instead of removing any of the bios chips, I piggy back to the first bios chip and was able to programmed it. After that, I pushed the power button and the system turned on. I added a SSD, re-installed the OS and I have been using it since then. I re-programmed the bios on the spare board but have not tested it or the spare power supply - I guess that they are probably okay. So it basically cost me a SSD since I already had a cheap programmer (not as nice as the one that you I believe you had on one of your videos) and a little time to get it working. So that lump of coal you have, may well turn out to be a diamond. :)

I really hope you do a followup for this. I'd love to see you bringing it to life.

Taking an EE approach rather than an IT approach, love to see it!

Did you put the CMOS battery and jumpers back in their correct place??

would the lcd image drive board not have master control of the leds so if that has failed it would explain the leds with no poweron drive signal and would explain the no image when backlight is overridden ???

Love to see a new dumpster dive-troubleshoot video... Always entertaining!

Does your generic barrel connector have a third wire for the sense wire? I have an hp ultra slim that the power supply went out on that has the same style connector. Not wanting to spend the money on a replacement, I used a brick with the same power output as the oem, used the original connector and just sliced in the sense wire to the positive and it worked.

The pin in the middle of that power supply connector doesn't pass current, it's just a supposed to have a resistor between it and ground to validate that it's the correct power supply for the device, all of the power goes through the inner and outer sleeves of the barrel connector.

Did you try reseating the ram? The all in one unit I found on the side of the road wouldn't boot until I reseated the ram in it.

As an experienced IT professional, I could not help but have a good laugh at this episode!.

Re-capping perhaps? Are there any Won Hung Lo caps in an HP?

For everyone who is saying to pull the mxm card, I really do not think that this is the issue. If the card was faulty, the backlight on the LCD would be coming on by itself and then not doing anything. It looks like just the screen panel isn't putting out a picture at all, not even asking for the backlight board to put on the backlight. Maybe the lcd tcon thing board is fried or something, I would expect the backlight to be coming on for a second if the video card has broken. I'd find a pin out for those dvi connections and create my own dvi cable for the back to test it and then probably turn it into a not all in one pc

No Dave, you didn't repair anything, you just took it apaaaaaaart

That mysterious down-facing USB port was actually where the dongle for the wireless keyboard and mouse these things shipped with connected. Its just another USB port, just in a spot dedicated to fitting the USB receiver.

What a great vid, this looks very similar to my Acer Aspire Z5771 23'' touch screen AIO running Win7 HP circa 2012 (ugly beast) that I stripped down last summer due to excess fan noise & overheating and sometimes crashing. After spending some half an hour trying to figure out how to get the plastic back cover off... what a palaver, sooo fidley and delicate. Eventually got it off and like the HP, it is covered with shields. When all shields removed, the fan and CPU heat exhaust were all clogged with thick dust build-up, so much so, I bought a new fan off eBay & whilst a had it all apart, I upgraded the Ram, put a new CMOS battery in, and best of all, cloned my OS system to a 1TB Crucial MX300 SSD. And 1 Crucial MX300 275 GB SSD used as a Misc storage drive. Best upgrade you'll ever do to a PC installing a SSD or M.2 (providing you're MB supports M.2) When powering up after the upgrade the system found the SSD's straight away and booted instantly...no BIOS adjustments at all (UEFI) except setting the clock. Now when I boot up, it only takes 23 seconds...fantastic, and running sweet as a nut. When I put it all back, I left the shield off to the M/B as these AIO's do get very warm. Didn't touch the CPU still CORE i5. Love your channel, love the humour and sayings you come out with, they crack me up. subbed ;0)

The title says repair...

Great find, me and a friend found a similar machine a long time ago, but it was a Dell. The motherboard was busted, but it had the cpu and ram still in it. 16gb of ddr3 so-dimm and a i3 3.30 ghz socket 1155.

Because of the title I kept waiting for your success! I mean I'll keep watching your channel, I didn't know about this one Probably would have watched something else had the title been better, but it might have been a video of yours because your channel is great and unique. A little like AvE, but for electronics guys, and still with the detail and charisma I know and love. Different detail and different charisma, but both you and AvE make KZfaq much better.

@EEVblog2 here is some things to think about Dave, 1st, the center pin is usually a comms pin to the psu,,, in dell they use it to tell what type of charger, without the comms it will power but not charge... you might have a 1.8 or 3v sense line going back from the BL board to confirm its on... the PC buzzer might be via the soundcard, plug some speakers in and see if you hear anything? have you got an old usb diag device that shows what commands going around the bus as its booting, it could be a courpt bios?

Swap out CPU, try each SODIMM on its own, take out the gfx card. It may do something. Failing that just put it back where you found it.

Want the camera or other reflections in the video, or without? Place a circular polarizer on the front of the lens; it's able to selectively reduce or eliminate most reflections. Makes a majority of outdoor shots look better, especially with sky or water

Dave, this barrel connector might actually have three separate pins. Outside barell, inside barell and center pin. This the case for dell power supplies, where power is transmitted over internal/external connectors and center pin sends data about type of power supply

Hi Dave, have you tried changing out the RAM?

Hi Dave. Select the ram modules and tighten the rubber contacts on the modules. Then put them back and try turning your computer on! If this dishonor will be a faulty graphics, cpu or base plate.

Tactic 1: pull the mxm card , clean the contacts with a piece of paper then pull out the ram and clean the contacts with a piece of paper ( standard 80g printer paper) then reset the BIOS. Tactic 2: pull the ram and clean the contacts, reset bios , pull out the mxm card and connect display to other output. In bouth cases do not start the pc untill you completed all the steps as described. You can also test with some other ram wich you know are good. And as described by other members , the mxm card usually fails because insuficient cooling . You can reheat the chip on the mxm card at 300-340 degrees C for 3 minutes and it should be as good as new.

Several models of the smaller HP all in one computers used laptop mainboards which in some cases means they are skimpy on processing power to avoid generating much heat. This ENVY looks much better than those.

Dave, check this out: kzfaq.info/get/bejne/nNSSibmossi-c3U.html I've also found a couple forum threads where people had identical issues, and one person replaced the motherboard and it worked, which suggests corrupt BIOS is plausible.

Anyone else think that 'APO' message on the multi-meter's LCD looks too similar to a negative symbol @14:30?

Seeing a scan line is a really big tell, also the screen isn't black upon power up its gray. I guarantee its the decoder card for the LCD (Crossover board, Serial decoder) and I bet both nuts it sits behind the heat sink and the solder joints went. I noticed this on a TV I repaired and they even had it affixed in a way that there would be axial stress on the board via not level standoffs and being in the hottest place in the TV (the exhaust vent at the top) you get the idea. A heatgun may do the trick.

12:30 UMA stands for "Unified Memory Architechture" and refers the fact that the internal GPU does not have dedicated memory. en.wikipedia.org/wiki/Graphics_processing_unit#Integrated_graphics

I think going after the backlight inverter was probably a red herring... The backlight enable signal would come from the board once it's done some rudimentary checks and initialised the GPU. A failed inverter is also easy to spot by shining a light onto the screen, you will see the LCD operating as normal but without any backlighting.

Dave, I would first hook up a PXE boot server to that Ethernet socket for diagnostics, then log everything and see it FOR SURE what works. Once you know that you could estimate whether it's worth the time and effort to move on with the repair. Also, in the log you might find useful information about the state of the GPU and perhaps the screen as well.

I found an msi version of this the other day i5 4200s in white... the back is missing though and i dont have a power supply yet to test it, its also missing the hardrive but everything else is there...

This video got me thinking I should try changing the Bios battery for my unit which had the blank screen of death and it worked. My unit would not even start. After dusting and vacuuming off the years of dust inside my unit I replaced the BIOS battery with a new CR2032 battery and it sprung back to life. I am so happy. Maybe everyone should try that solution first. Also that separate secret USB port is for the wireless keyboard dongle. A bit of a crazy video, but fun. Thank you.

A lot of people are saying to remove the discrete gpu to use the integrated graphics, but I don't see how that could be our problem. Every time I've ever seen that be the issue, the integrated/onboard video port has always been enabled just to display a message saying to switch the cables to the discrete gpu. Thoughts? Corrections?

Timestamps for uhm & uhh supercut: 0:05 , 0:12 , 0:15 , 0:17 , 0:36 , 0:39 , 0:59 , 1:08 , 1:13, 1:20 , 1:23 , 1:37 , 1:43 , 2:07 , 2:20 , 2:26 , 2:41 , 2:43 , 2:49 , 2:51 , 2:55 , 3:45 , 3:52 , 3:58 , 4:06 , 4:21 , 4:57 , 4:59 , 5:04 , 5:14 , 5:21 , 5:30 , 5:36 , 5:46 , 6:04 , 6:08 , 6:15 , 6:25 , 6:33 , 6:37 , 6:51 , 7:04 , 7:17 , 7:37 (x2 rapid succession), 7:45 , 7:50 , 7:58 , 8:34 , 8:49 , 8:59 (x2 rapid succession), 9:05 , 9:11 , 9:18 , 9:28 , 9:41 , 9:45 , 9:49 , 9:50 (x3 rapid succession), 10:01 , 10:03 , 10:11 , 10:14 , 10:19 , 10:33 , 10:48 , 11:05 , 11:46 , 12:00 , 12:04 , 12:20 , 12:23 , 12:26 , 12:32 , 12:53 , 13:06 , 13:22 , 13:26 First half stamped, get to work editing Jens! Personal favorites: 0:12 , 0:59 , 1:23 , 1:37 , 1:43 , 2:07 , 2:43 , 2:55 , 3:45 , 3:52 , 5;14 , 5:46 , 6:15 , 6:51 , 9:41 , 10:14 , 10:19 , 10:33 , 11:46 , 12:32

chop chop dave with a repair vid too.... u got us all hook, line and sinker

What happens when you plug into an external monitor , VGA or HDMI?

Hello Mr. I have the same device that was sent to me from Europe. Briefly, it has been almost a year in the container, when I received it it was not starting, no led on the power button, no signal nothing at all. I opened it and cleaned the motherboard, now it starts up properly, the processor heats up, the rams are detectable but the problem is the display that I don't have. I have no display on the screen or with the keyboard. Can you help me do something please? some tips for me to have the poster thank you. Cordial,

my laptop done similar to this, the mother board will go, it semi boots but just sits there with lights on but no further, so sad it dosnt work because when they do they are a vary good laptop

I wouldn't be surprised if you had 2 or more faults present. Backlight and perhaps the graphics card. Maybe even a bung screen. It gets fun when you've got multiple symptoms throwing a spanner in the works. Having been a contractor who fixed these, I'd typically shine a torch into the LCD, and look for that familiar round HP emblem upon power up. That's your 5 minute backlight test... I have had a similar model show these exact symptoms, and I ended up escalating for replacement simply because of the economics of repairing these things. Ideally, you want to be able to pop it open, change a module, close it, boot it and sign the job off.

If there is no storage device how could it boot into windows?

That Secret USB port is for the Wireless mouse/keyboard. i had one of those but olddddder model at my Test Lab. Dead as a Dodo tho.

Try removing the MXM card and connecting the LVDS cable to the UMI port. You could also test the processor in another system, that your are willing to part with if the processor is bad.

Curious. Did you try a tv input converted to lvds

The 'secret squirrel' USB port on this series of HP AIO is for the bundled HP wireless key/mouse dongle, the machine complains if its missing. Also, typically check what the included video port actually is, on some AIO its a video OUT to connect a 2nd screen, on others its a video IN , so that the screen can still be used if the machine becomes trash.

The way that line fades out slowly on the LCD makes me think the screen is knackered. And of course if that's the case I doubt it would emit any error beeps as the display isn't something that it would detect a problem with.

As all other people says here, try to remove the mxm card, and connect the cable to the integrated graphics. The integrated graphics is disabled when a separate video card is installed.

Would definitely love to see a followup on this

I have the power brick for that thing. I go to second hand shops and buy the entire box of power bricks. 19.5V 9A It's even an HP. This thing would drive me crazy. A touch scream PC that has a TV. The fingerprints would have me around the bend. HP stuff from that era are garbage. They really dropped in quality. They picked up there socks just this year finally. Their CEO's have been incompitant.

If memory is defective it won't show anything on the screen and if there is no buzzer/boot code read out then there will be no signal that it is a memory fault. Usually, laptops and thin and lights have some light sequence to show error codes but an easy way to test is to remove the memory modules. There should be some sort of error. If it is still the same then it is possible that it is a memory fault. As far as other comments saying to pull out the video card, that might not fix it, it is possible that the bios decides what to use, even if there is no dedicated graphics card. If there is a way to flash the bios you could flash one from a device of the same series but with integrated graphics.

New dumpster video! this should be in the main channel!

No, that's not the NSA edition webcam since it can be easily found and unplugged. The fact there's no way to disable the webcams and microphones in most computers says a lot. Probably a business computer which is why you can unplug it if you want.

Soft power control is done in hardware, not by the CPU or BIOS. So the fact that it does power on and off sadly only means as much as PS_ON works and the PWR_OK and +5VSB lines are good. Next, after soft power-on, the CPU should get come out of reset in which it is kept beforehand, and the clock for the CPU starts running as well. It is only then that the CPU comes into play and slightly later on, the firmware.

Did you fix the trace you cut? Fan was spinning before you did that.

The internal graphics output is usually completely completely disabled when a discrete card is installed. If the AMD card is bad, then neither output will work.

Check the RAM modules. I have repaired some 2012 HP Pavilion G6 laptops that would power up with the fans at 50% speed, HDD activity was showing as well, but no image or back-light whatsoever so it can be as simple as swapping the memory sticks.

I had seen that when updating to Windows 10 the bios craps out and the screen won't work I have one right now I have to work on. They say to use Linux and a arduino to reflash the new bios to the chip and it should work after that.

Why make a simple diagnostic test into more work. Simple rule of testing. Removed the cmos for a couple second, Plug it back in. Test 1, Removed the memory 1 by 1 to determine if ram slot is bad or the memory test 2. Final test, Re-seat component cpu and memory. To determine if hard ware failure. In this case, It power on and no boot, Plug into external monitor.

Maybe it still won't boot with the leds powered seperatly because the main board is expecting some feedback from the led driver board?

Two weeks ago I scored a HP Z1 Workstation (G1), 27", not touch screen. It was the RAM. Take out the RAM sticks, put them back in. BOOM, powers up. Otherwise it was black screening and the fans were going full speed. Fixing HP problems - check RAM first

Why not use a second Monitor at the PC´s external HDMI Port to see if PC and Graphics card are running?

"Did you see a scanline? I saw a scanline." And i'm sitting here actually nodding "yeap"...

EEVblog2 why don't you try it without the TV tuner card (had the same problem with another HP touch AIO)

Have you actually checked it’s power supply yet? It may be missing a rail.

+EEVblog2 - The tiny center pin is ether for Adapter-Identification / Hardware-DRM (like Dell) or standby

This power supplys plugs are used in Dell to,central pin is for authentication .You do not need to connect the welding machine to it.

did you check ram - put only one module of the two?

The 'secret squirrel' USB is for the wireless dongle for the kb/m combo that it came with.

lol you find such awesome things in dumpsters. Were I live it sucks because it's against the law to dumpster dive. I knew a guy who got locked up for it. When I was a kid we lived in a different town and I used to find all awesome things like you. For a little kid it made it feel like Christmas. I miss them days. But who doesn't miss their childhood. Love you're videos they make my day. Thanks.

Even with dead backlight you should still see some sort of image if you look at the right angle. It would be nice if you could fix it though, something for Sagan to tinker with

Looking to me like a MXM card failure. Remove the MXM card and plug to LVDS to IGP port it should work. Reason i am suggesting this is because the MXM card being in the slot will disable the IGP removing it will force IGP to work again.

remove MXM graphics card

I have worked on these. 90% of the time, it's the motherboard. If you think it's the MXM card, you have to also move the LVDS cable from the MXM output to the Internal graphics (normally marked LVDS). But these were horrible about the ACAD going out and taking the board with it.

Replace ram and try again, remove graphics card,reset cpu. Those are the first steps i would take.

I had a non mxm version of this come through once, bad motherboard. Not excactly sure where the issue was but I could not get it to power on. It did smell like something went boom but no skid marks. Those power cords are used on Dells, if that center pin breaks they do not charge the battery on most models. PITA to fix since trying to solder on 3 wires to those barrels sucks when you want it to look decent.

It looks like it's working at least somewhat by the disk access light, and usually on computers like this if there is a beep code it will come over the speakers. The only time I've had my computer (Pavlilion 23-f364) beep is when it's turned on with no RAM installed.

Did anyone mention to plug a keyboard up to see if keyboard posts lights and also agree with removing the gpu then hooking to internal.

would it be possible to use the screen and touch with another computer without bespoke driver board?

I promise you that this will be a RAM issue. I have been working on computers for decades and the symptoms of bad RAM vary so widely there is no way you could list them all. I've had RAM that wont POST. RAM that will POST, but blue screen as soon as I hit a certain memory usage, no symptoms, I've seen it cause internet disconnects, graphics card issues, driver issues. You name it. Pull the sticks, try a different pair. Or if you can, put the HP's memory in a suitable laptop and fire up memtest and see how that works out