Pc won't boot up. Fans come on and power supply was checked for correct voltages. I swapped CPUs and memory sticks. When I boot it up I get one long beep and then 4 short beeps.

The AMI BIOS 4 beep error code usually means an issue with memory. If you are not getting any video, then the problem is probably in the first bank of memory. If you have 2 memory sticks installed, try swapping them. If not, try re-seating the memory stick. A single stick should be placed in the "A" channel slot, the one closest to the CPU. You aren't saying if this is a new build. If so, are you certain that you have the correct type and speed memory? The manual, pages 1-3 thru 1-5 lists the "approved" type/size/vendors for memory. Vendor isn't always important, but if type and size are correct, and the vendor is not on the tested list, there may be compatibility issues. Some memory requires different voltage settings than the MB defaults to. Check the memory vendor for details if necessary.

Could be your motherboard. Does anything come up on the screen at all when you boot up? Do you hear a beep at startup? Also check to make sure your hard drive is spinning just to be sure.

all in one, are no fun to fix. a real DT is vastly more easy
and standardized ... ATX , for example.
cute sure, but hard to work on,
there are no schematics, they are secret. (called proprietary)
last thing HP wants is illegall clones, no?
why not get the full HP.com service manual.
it tells you the PSU voltages. to check.
all must be good.
what if the CD drive is bad, you will get CRC errors reading it.
why not boot to a USB stick
put any live OS on the USB stick. linux or windows 8 or 10 PE, boot disk.
then boot to the stick , omg the computer is ok. just a dead CD drive.

that be like 1st off the bat
all shops keep boot USB sticks, all do.. or diagnosis goes , to H3LL..
BIOS screens all look good,. bios memory check passes.
Bios, shows memory size matches whats there.
try running one memory stick at a time.?
it 2 memory sticks? try both1 at a time.
make sure CPU is not overheating, and fans ok.

if say the OS boot sticks (way windows 8 PE live works)
or any do and a new HDD will not load any OS.
then the SATA port must be dead.


if all above checks out, the PSU is toast.
Power supply unit.

Count the beeps assuming that there are a certain number, and check on the motherboard manual to seewhat they mean...
Likely causes
Fan(s) clogged up- clean everything thoroughly and check cpu fan and all fans including power supply
Check power supply voltages
Memory failed, swap it out or remove 1 stick at a time if there are 2
Motherboard failed due to bulging capacitors
I hope I have been of help but please do not hesitate to ask if you have any further questions.
I appreciate your vote if you appreciate my reply.

remove the memory stick sticks if 2 remove 2 at time when mmachine is OFF. replace when OFF bad sticks will do this.

Here try my trouble shooting steps. Some I usually follow this when I can't get a power up. My no-boot flow chart has always worked for me (many years work for Gateway tech support has paid off).

So basically you cannot get the pc to POST. Meaning you have just a black screen when you power on the pc, right?


1. Full power down. Unplug the power cord from the Power supply. Then hold down the pc power button (this discharges any residual power in the capacitors).

2. Open the case and reseat the graphics card, hard drive, and RAM.

3. Take out one of the RAM sticks if there is 2 or more. Swap the RAM sticks in different RAM slots. Try one stick at a time to see if you can get the PC to boot. If this works, then the remaining ram sticks are damaged.

4. Set the Cmos jumper to clear. Power up the pc. Power down the PC. Set the Cmos jumper back to normal position, power up the PC.

5. Unplug and replug all the power supply cables.

6. Check the powersupply function. Either by a powersupply voltage checker (20-25 dollars at local PC shop), get the supply tested at a PC shop (usually a free service), put the powersupply in a different pc, or try a different powersupply in the problem computer.

If the Powersupply checks out ok, then you will have to do a process of elimination to find out what part or parts are the culprit of the No-Boot.

Start by pulling all the ram sticks if you have not already. This is the easiest components to check and usually a culprit.

Take out one of the RAM sticks if there is 2 or more. Swap the RAM sticks in different RAM slots. Try one stick at a time to see if you can get the PC to boot. If this works, then the remaining ram sticks are damaged.

If it is not the RAM, you have to continue removing items such as sound cards, un-plugging hard drives and optical drives, other PCI cards. Do this one at a time until you find the culprit. If a POST screen, meaning you can see Anything from the PC brand name to Motherboard brand name appearing on the screen.

Hope this works. I am thinking the ram is probably toast. We will see.

Brian

I am almost positive it is the ram, because it gets to windows but crashes after loading windows partially. I once had a similar problem. Just make sure all the Power Supply connectors are properly connected.

Try these steps too:

1. Full power down. Unplug the power cord from the Power supply. Then hold down the pc power button (this discharges any residual power in the capacitors).

2. Open the case and reseat the graphics card, hard drive, and RAM.

3. Take out one of the RAM sticks if there is 2 or more. Swap the RAM sticks in different RAM slots. Try one stick at a time to see if you can get the PC to boot. If this works, then the remaining ram sticks are damaged.

4. Set the Cmos jumper to clear. Power up the pc. Power down the PC. Set the Cmos jumper back to normal position, power up the PC.

5. Unplug and replug all the power supply cables.

6. Check the powersupply function. Either by a powersupply voltage checker (20-25 dollars at local PC shop), get the supply tested at a PC shop (usually a free service), put the powersupply in a different pc, or try a different powersupply in the problem computer.

If the Powersupply checks out ok, then you will have to do a process of elimination to find out what part or parts are the culprit of the No-Boot.

Start by pulling all the ram sticks if you have not already. This is the easiest components to check and usually a culprit.

Take out one of the RAM sticks if there is 2 or more. Swap the RAM sticks in different RAM slots. Try one stick at a time to see if you can get the PC to boot. If this works, then the remaining ram sticks are damaged.

For non-BIOS issues:

If you did not try to update BIOS before the problem started then try these troubleshooting steps.

1. Full power down. Unplug the power cord from the Power supply. Then hold down the pc power button (this discharges any residual power in the capacitors).

2. Open the case and reseat the graphics card, hard drive, and RAM.

3. Take out one of the RAM sticks if there is 2 or more. Swap the RAM sticks in different RAM slots. Try one stick at a time to see if you can get the PC to boot. If this works, then the remaining ram sticks are damaged.

4. Set the Cmos jumper to clear. Power up the pc. Power down the PC. Set the Cmos jumper back to normal position, power up the PC.

5. Unplug and replug all the power supply cables.

6. Check the powersupply function. Either by a powersupply voltage checker (20-25 dollars at local PC shop), get the supply tested at a PC shop (usually a free service), put the powersupply in a different pc, or try a different powersupply in the problem computer.

If the Powersupply checks out ok, then you will have to do a process of elimination to find out what part or parts are the culprit of the No-Boot.

Start by pulling all the ram sticks if you have not already. This is the easiest components to check and usually a culprit.

Take out one of the RAM sticks if there is 2 or more. Swap the RAM sticks in different RAM slots. Try one stick at a time to see if you can get the PC to boot. If this works, then the remaining ram sticks are damaged.

If it is not the RAM, you have to continue removing items such as sound cards, un-plugging hard drives and optical drives, other PCI cards. Do this one at a time until you find the culprit. If a POST screen, meaning you can see Anything from the PC brand name to Motherboard brand name appearing on the screen. The PC may not boot to windows, but it Does post at this point, and with that the problem is resolved. If windows does not load, then you have a new problem. Best dealt with asking a new question.

Good luck!
Brian

In computers, any number of problems can cause this - bad RAM, bad hard drive, fried voltage regulator(chip in a laptop), overheating cpu, overheating video card/gpu, there are even a few device drivers that can do this if they become corrupt. Usually, however, its not an issue with the power supply/power source.

I would try swapping the RAM with new(or known good) sticks. Also, make sure the system is clean, and no dust has built up in it, especially in/around the fans.

If the RAM swap is unsuccessful, and the system is clean, check and make sure the fans spin when the system is on.

Power down the system, disconnect the data and power cable from the Hard Drive, and turn the computer back on - you won't get into the OS, but you'll be able to determine if the issue occurs w/o the hard drive connected.

Ultimately, it may come down to a bad motherboard.

It sounds like you?re an experienced hardware guy so I won?t bore you with the basics. When I?ve gotten stuck on a new motherboard no-booting problem these steps have helped me: -Make this as basic a machine as possible. You don?t need much of anything to get the POST to display and anything else just adds more variables. -double check the processor and memory, ensure they are correct for the board. Make sure the manual is the correct one for your board. -Try setting the BIOS to the manufacturers ?Safe? settings or default settings. You might even want to pull the backup battery out, unplug the power supply and let it set for 30 minutes to void the BIOS settings. -Verify the power supply is working correctly, preferably with a power supply tester. If you can?t then try putting this power supply in another computer to make sure it not only turns fans on but really supplies the correct voltage needed to make things work. -Buy or borrow a pre-boot test card. This is a diagnostic card that plugs into a PCI slot of your PC and will give you a much better diagnosis of what is going on. You can usually pick one up for about $35. - Make sure your CPU fan is plugged into the right motherboard connector, the newer boards will check for the CPU fan. I would suspect that if this were the case you would see something on the screen but you never know. Last but not least you might actually have a defective board. Granted it doesn?t happen too often but I?ve had two or three dead out of the box over the past few years. Chances are if you?ve gone thorough all of this and relate the steps to Tyan support they will send you a replacement. And if the new board does the same thing then you only have two remaining variables left; CPU and memory. Good luck and if you have any other questions please let us know.