Compaq CQ56 does not boot, even bios not reachable

[dw-CQ56]

Sehr geehrte Damen und Herren,

I own a CQ56-203SG Laptop which was doing fine for years (I do not remember when I bought it). No misuse, no hard hits. New HP Battery since a few month.

No difficulties before. Used it with Ubuntu which worked perfect! No M$Windows ever touched this machine.  

It does not boot any more. Even BIOS is not reachable.

Start by pressing the power button leads to: Light in power button is on, orange light in key F12 is on, white light in CapsLock key is slowly blinking. No signal by coded blinking recognised. 

Fan is on, slowly, constant.

Monitor remains dark. HD lamp does one short flicker when powered on, remains dark then.  

It does NOT make a difference if lid is closed or open. 

Obviously even going to BIOS is not working. 

Last status before failure:

OS working, lid closed, machine was sleeping.

Did not wake up. After several attempts it woke up exactly once. After restart it remained dark for ever. 

Formerly all that worked fine for years. 

I tried to power down completely including battery remove and then press power button to drain capacitors. No result. 

I tried the Win + b keystroke combination, no result. 

Machine dead. 

Modell LD710EA, Ser (Personal information removed)

What can I do?

Hope for your help!

Mit freundlichen Grüßen
Dietmar Wilkens, Duisburg

[T4M]

Most common problem is dead GPU , was it hot before it died or/and u cleaned it recently?

[dw-CQ56]

Hallo, thanks for the swift reply. 

likely the machine was not hot, it was sleeping. Display was actually not active while lid was closed. Nothing felt hot at that time. So I doubt something was heating up.  

I never cleaned the GPU: I do not know how to get there. The fan and the cooler do not look like significant amounts of dust are somewhere. 

It sounds expensive... I purchased the machine for E200 net but I liked it very much. 

If your assumption is right:

How would a repair look like?  

Exchange of single component possible or is a change of MoBo necessary?

Appreciate more hints!

Thanks for taking care, 

Mit freundlichen Grüßen
Dietmar Wilkens, Duisburg

[T4M]

Well since u never cleaned it , i can asure it has dust inside , even tho it looks clean from outside , its much worse when u reach it from inside =)) , as for repair if its really dead gpu i wouldnt bother with this laptop , in order to properly repair it u need reballing of gpu and that is not cheap.

Btw u didnt write model of it if its nvidia/ati then its most likely the problem , if its intel then its your lucky day.

[dw-CQ56]

Hallo T4M, 

1) You are right: There was dust. I disassembled the whole laptop and found where the dust is, where the CPU is and where the GPU is seated. It is all AMD. While the CPU looks like pluged in the GPU seems to be glued?!

2) Is there a way to exchange the GPU? Ca I buy the spares and assemble them? What special tools are necessary?

Appreciate your hints!

Mit freundlichen Grüßen
Dietmar Wilkens, Duisburg

[T4M · Accepted solution]

Yeah gpu is soldered to motherboard.

Well you can heat it up with home tools , this might revive laptop , but thats just temp fix , to properly fix it you need to completely take off gpu and put in new one , and that must be done with reballing station which as i said is not cheap.

If you want to go with home fix theres plenty videos on youtube with heating process.

[dw-CQ56]

Hallo, 

the situation is resolved. So I want to let you know about the results: 

1) Your assumption there might be dust in the cooling system turned out right. It is not visible, not even if you disassemble the mainboard! But it is there.  And it actually was the cause of the total failure! 

2) Yes, the GPU has failed operation. Your assumption was right, too. 

3) Trying to heat up the GPU to re-solder the hidden pins ended up with a molten CPU socket. So I'll never find out if it worked ....

4) The forum guys unfortunately did not find a way to look up the spare parts needed. Well, no problem, this should be in the responsibility of HP company. They charge for it so it should be feasible to get answers ....

5) The web site has circuular references but almost no information about my Compaq Presario CQ 56. The telephone help line is neither skilled nor responsible. And they have no information at hand. Total failure. At least a cheap  land line connection. And the local companies you are referred to by HP as a private individual  customer are pure wholesale companies. They can not do much. HP does not know about their own "partners". 

HP you are doing a really poor job. Nothing but bull**bleep** information. HP fails completely and in an annoying way to help with spare parts. 

5) With the help of a non-HP person I managed to get the order number and prices for the mobo (and the CPU and shipping times etc.).

So I ended up ordering the mobo via Amazon (!). 

6) Knowing the order number and ordering via Amazon (from a company just 20 km away...)  led to a quite quick shipping of a brand new, perfectly wrapped and completely equipped mainboard. Only CPU needs to be shifted, no problem. 

7) HP sucks - but the machine is working fine now!

Thanks to the people here - you (Mr. T4M) did a very good job. 

Best Regards

Dietmar