Laptop wont show POST after cleaning

gimpshrimp

Distinguished
Jan 10, 2010
10
0
18,560
Hello everybody,

10 years old Sony Vaio VGN-A197VP
Disassembled it yesterday
Removed a ton of dust from it
Replaced thermal compound with a new dose

Result when pushing ON button:

Fans/HDD start to Spin
Black Screen/No Post
Computer Restarts within 3 seconds
Fans/HDD start to Spin again
Black Screen/No Post and stays like this

x5-Checked all the cables, screws, connections / reseated the heatsink and it didn't help.

Disconnected CMOS battery to reset BIOS settings, nothing changed.

Removed: HDD/DVD drives, BT/WiFi/CardReader Modules (RAM sticks are OK). Still Nothing.

Keep in mind, this laptop has been working perfectly fine until I disassembled it for cleaning.

Any thoughts? :( Thanks!
 

gimpshrimp

Distinguished
Jan 10, 2010
10
0
18,560


hello icraft :) thanks for quick reply

I checked and didn't see any metal parts touching right now. Laptop is completely "naked" at the

moment, no screws, only CPU+heatsink+RAM+GPU+Power adapter+keyboard are ON and still wont POST.
 

gimpshrimp

Distinguished
Jan 10, 2010
10
0
18,560


Hello, thanks :)

I have never connected my laptop to an external monitor! I only use the laptop's screen!
 

gimpshrimp

Distinguished
Jan 10, 2010
10
0
18,560
Dear everyone,

I am willing to pay $20 for a step-by-step diagnostic guide that I will strictly follow! (till we get a possible solution)
Once I get this laptop to work, I will choose the correct answer and then I will ask (via pm) the paypal address of
the person that found the solution, so I can deposit this small amount to his account!

Thanks! :)
 

gimpshrimp

Distinguished
Jan 10, 2010
10
0
18,560


Hello, I have already checked both RAM sticks on another computer and they are fine!

I also connected an external monitor (15 pin) and still black screen remains.

Laptop restarts within 3 seconds on cold boot & after restart black screen remains. (no POST)

It worked like a charm before I disassembled/re-assembled it in order to clean it.

I don't know what might have gone wrong. What could it be? Here are 3 high res pictures:




http://imageshack.com/a/img835/2637/xry7.jpg

http://imageshack.com/a/img841/681/csz5x.jpg

http://imageshack.com/a/img838/125/jymi.jpg
 

gimpshrimp

Distinguished
Jan 10, 2010
10
0
18,560


Isn't the CMOS battery that green thing next to the RAM stick? How can I check
it's voltage with a multimeter? I will borrow a multimeter from a friend tomorrow
morning. I remember checking BIOS long time ago when laptop was working,
the only available settings are Date/Time/Boot Priority. I didn't remove the CPU.
I only removed its old thermal paste and applied new dose of thermal paste. I
had to rub it quite hard because old thermal paste was like rock solid. Thanks!
 

gimpshrimp

Distinguished
Jan 10, 2010
10
0
18,560


The battery is not capable of maintaining BIOS settings any more.

It's been like this for last couple of years! (laptop is 10 years old.)

But even so, if I disconnect CMOS and boot, laptop still wont POST!

So OBVIOUSLY something went wrong during assembly/disassembly,

but I can't find out what! Screws/Connections/Sockets seem to be OK.
 

gimpshrimp

Distinguished
Jan 10, 2010
10
0
18,560


Sure I will check again and will get back to you!
 

gimpshrimp

Distinguished
Jan 10, 2010
10
0
18,560


Hello, here are the pictures you asked for:

http://imageshack.com/a/img842/9336/lnne.jpg
http://imageshack.com/a/img838/179/t526.jpg
http://imageshack.com/a/img838/6422/h7uf.jpg
http://imageshack.com/a/img845/6751/x8e7p.jpg

One thing I noticed is that when I push ON button, keyboard lights do not blink
or turn on, not even Caps/Num/Scr Lock turn on when I push them!

You said I should try turning laptop on with no CPU heat sink attached?
(I guess you want to know if I can get to see POST?, and once I see it, to immediately
unplug power?) Are you sure about that? Wouldn't that fry my CPU? Thanks!
 

gimpshrimp

Distinguished
Jan 10, 2010
10
0
18,560



OK so I removed the CPU fan + heatsink, pushed ON and waited for like 15 seconds
before unplugging it, and POST didn't show up. So, to summarize things:

-Laptop used to work perfectly fine until:
-I opened it up in order to removed a ton of dust and to apply new thermal paste

Now when I push ON:

-CPU fan starts to spin, no POST
-laptop restarts within 3 seconds
-after restart, fan starts to spin again, no POST, just black screen
-keyboard lights permanently off/no beeps

So far: I have removed *all unnecessary* devices just for POST purposes
I have checked all cables/connections/screws 5 times
I have tried connecting an external monitor
I have checked RAM sticks (they are good)
I have tried the 60-second ON button push
I have checked for any electrical circuits ... and still no luck!

I did something wrong during disassembly / re-assembly, that's like 100% for sure.