HELP !!! - My NP8760 is beeping at me

My 3 year old NP8760 is crying out for help

I have had the problem with the "Expanded battery" for a while now but the system used to start with the battery in place, though it gave me only 10 mins of backup. Recently I could not start the system, I assumed it to be a case of dead battery and tried to start the system on direct A/C power, but have been unable to get the laptop functional.

On direct A/C power, by the time windows boots up and reaches the login screen, the lights for Caps Lock, Num Lock, Scroll Lock start blinking and the system goes into a non-stop beeping mode (beep... beep... beep...) and then auto shuts down.

I looked up the symptom, and it seemed to indicate that the fan might have stopped working. I opened the back panel to confirm, and lo behold the CPU fan (one away from the battery) does not start up at all.

After a brief discussion with Sager tech support, I purchased a new fan and Battery, which was delivered to me yesterday. set me back by $200

- Once connected, the new fan did not run.
- I switched the new fan over to the GPU socket and it worked as expected.
- The Old fan also works when switched over to the GPU.
- This test reveals that the problem is more likely with the power supply from the board to the CPU fan and not the fan itself
- The system is currently down, and I need assistance with it
- I have not been able to test the battery as the system is down.

I was able to spend some more time troubleshooting the laptop. Since it was determined that the issue is not with the CPU fan I have reinstalled the OLD CPU fan.

The following was the scenario and the observation:

- Removed the back panel
- Powered the laptop
- Entered BIOS and Enabled Boot time diagnostic screen
- Save and exit
- System restarts, no beeping yet, CPU fan still not spinning
- Computer starts up, POST diagnostic is shown on the screen now
- After about 20 seconds into the booting process, the beeping starts
- NOW the GPU fan starts spinning faster.
- CPU fan starts spinning as well
- System continues the booting process
- windows boots up and I am able to get to the login screen
- the system auto shuts down after two cycles of continuous beeping

I tried removing the RAM modules and placing them back. The result was the same.

Question:
Does the CPU fan run only when needed and not constantly on? is this the behavior normal?

Has anyone had similar issues ? This YouTube video was the closest I could find that looked like the problem I am facing --> Sager NP8690 - Beep and Crash (from boot to crash) - YouTube!

Initially I thought I might need a new MB, but the way the GPU fan spins up when the beeping begins seems to indicate the GPU is the culprit here... Any suggestions on what I try next to narrow down the problem ?

If I need to replace the MB it is likely to cost me close to $400 plus shipping and labor which might end up becoming $600 + the additional $200 I have already spent on it.... that is looking like it is taking it to $800 Seems too steep a price to fix up my 3 year old baby :cry:

Any help is appreciated.

Thanks and Regards!

 

Not sure if the issue but it sounds main board like. The only thing supplying power to the cpu fan is the motherboard. If it's not getting power that that's a problem. You can definitely find those parts cheaper if you look online. I recommend watching some disassembly videos and downloading the manual for that laptop and doing it yourself. It's easy if your careful and slow. No need to pay for labor

Sent from my SPH-L900 using Tapatalk 2

 

Online seems to be more expensive so far, unless I am getting a used MB from eBay

I am generally pretty good when it comes to putting things back together and might end up doing that in this case, if I can get someone to help me conclude it is the MB. I do have the service manual from ManualW870CUandW860CU.pdf but it does not seem to have a lot of details on putting together the entire laptop

I would appreciate if someone can point out if, under normal conditions, the CPU Fan is expected to be running all the time ? or does it power up only when needed ?

 

The CPU fan should always run. The RPM will adjust depending on the load, but it should still spin even during idle or Sleep, as the CPU is constantly in an active state, producing heat. I agree with dandan112988; it sounds like a board issue to me.