Screen blackout all of a sudden.. no display...

Hello all,

Model - Compaq presario v 2000
RAM - 1 GB
HDD - 60 GB IDE

The problem:

Laptop was working fine until one fine morning it wont boot up

The symptoms:

Upon switching on the laptop, the power LED at the top of the keyboard glows & is permanently ON.
The HDD LED glows for about 10 secs and is then off.
No display seen on the LCD
The fan rotates for a couple of secs after switching ON and switches off as well.
No other eminent sound of the laptop running.

What I have tried:

1. Connected a secondary monitor and switched the display onto it. Still no display.
2. Removed the HDD and booted. Same symptom exists.
3. Removed memory module, cleaned it, re-inserted into the other slot. Nothing positive.
4. Swapped a different memory module. Nothing changed still.
5. Removed all the memory modules just to test whether the motherboard would sense a nil RAM inserted condition. Yes, it did and beeps were sounded for the same.
6. Tried booting with a bootable windows disc. The sound of the CD-ROM drive spinning was heard but then no booting / display would occur.
7. Pressing F10 to enter into BIOS setup would also not work.
8. Tried a hard reset too.
9. Made sure the fan is clean.
10. Tried with the battery and AC power and its all the same with either of the power source.

What I am not convenient with:

Getting even more deeper under the hood of the machine.

Help !

oops.... I must say I'm not comfortable getting under the hood of the machine..
Is there any possibility of determining whether the motherboard/CPU is at fault without having to open the hood?

Hi all, sorry for a late reply. Am back again with the status update on my laptop repair. Just got information today from my service guy that the motherboard is faulty and needs to be "re-worked." Upon asking the specifics, he stated that the power section of the mobo was faulty and the repair would cost around 35 USD with a testing warranty of 1 month. Should I proceed with this?

Decision is confusing on my part because the term "power section" is not new to me!
Please allow me to explain :

- The motherboard that my laptop uses now is just over 9 months old. Replaced brand new with a warranty of 6 months. That's right.. am out of warranty as of now.

- Why I had the original motherboard replaced : It also had this similar booting & display problem and a "power section" re-working was required! I choose to replace it rather than repair and now the new motherboard shows some the same problem in the same section ?!
Note: My faulty old motherboard was returned back to me during the replacement.

Now, this guy says such a problem could be caused repeatedly only due to 2 reasons:

1. A faulty adapter (which I believe is less likely since it was tested as OK during the motherboard replacement service earlier)

2. A faulty / fluctuating power source - (which is also less likely since I have been using the laptop @ home most of the time and have several electronic equipments & 2 other desktops running perfectly fine)

However, the guy says a faulty adapter cannot be tested "OK" just by checking it once. It will give out fluctuating voltages "Intermittently". And for point no.2, he says desktop's have stronger SMPS when compared to a laptop. So, advise is given to me to use the laptop plugged into a spike buster circuit - an additional expenditure again.

Please enlighten me & advise whether to go ahead with this repair or not ! I do not want this same problem occurring for a 3rd time again. Not surprisingly, I am not able to think of other reasons for the power section of a laptop motherboard to fail repeatedly .. (could it be because of devices that I connect to it like pen drives, cooling pad, wireless internet device, bluetooth dongles, an ipod, my mobile ....)

Firstly, let me be clear that I do not use all those devices at the same time ! It could be 3 devices at the max. at a time.
That being said, mine is the original HP adapter that came with the laptop. A 65w one. Something like this although the part no. does not match.
http://www.shopping.hp.com/product/c...DL606A%2523ABA

The price on the website surprises me as the guy at this service store quoted a price of 35 USD.
Also, he advises me to go in for a surge protector which would cost me another 10-20 USD depending upon the make of the product.
Would I go for an adapter or a surge protector ?

I would also like for you to know that, both in my old and new motherboard I have been having this problem of "sudden shutdown" of laptop.. yeah.. the usual overheating probs... Whenever the cpu frequency shot up on load (Intel mobile processor with a speed step feature), the laptop would just switch off.

How I diagnosed and resolved it :

I noticed that the notebook would switch off only when under load with some intensive application.
Hence downloaded the "CPU-Z" application to monitor the frequency of the processor.
Noticed that there was a "Speedstep" feature on my Intel Centrino Mobile processor that kept varying the speeds between 600 Mhz to 1700 Mhz by changing the multiplier values and all that. . . . as u would be knowing..
Got hold of this wonderful application "Speedswitch XP"
http://www.diefer.de/speedswitchxp/ and used it to maintain the frequency at an all time low by opting for the battery optimized mode as explained in the webpage above.
That solved the problem instantaneously ! and i was much glad to have the notebook running just fine for a month until now... except for the fact that this time..

A sudden shutdown did not happen but the laptop itself went dead !

I'm sure that there was no dust clogged onto the fan nor was it a case of thermal pasting on the processor (since its expected to be done when replacing a motherboard) . plus I did get myself a cooling pad too !

Now, how far would you say a faulty adapter would have caused "such a shut down problem" ?
(I'm focusing at the adapter bcuz I have had both the "sudden shutdown problem" and "power section on the motherboards being affected" with both the motherboards)

It was highly unlikely that I had a bad RAM module cuz I upgraded the RAM also ! to 1 GB from the older 256 MB along with the motherboard upgrade. As I said, everything in the laptop apart from the HDD, DVD drive, battery, adapter and CPU are new !

Overheating - How else should I rule it out apart from making sure that the fan is clean, using a cooler pad, making sure thermal pasting is done

That being said, is it possible for a faulty adapter to cause such a problem at all ?
(Do adapters just have a step-down transformer alone or do they have other functions such as varying the power output as per the laptop's requirement now and then ? )

It wasn't a motherboard upgrade.. but just a "replacement" ! pretty much the same part number was replaced... so i guess current requirements should be the same..?

Alright.
Instead of spending 40 USD+ on a new 90w adapter, can I connect the existing adapter via a surge protector costing about 20 USD.. would that solve problems ?

You mean borrow a 90w adapter ? Afraid I don't have friends willing to share their adapters... ! Nevertheless, I hope you agree with me that the laptop, once re-worked will work fine with my existing adapter itself.. Only catch is that we are not knowing how to eliminate the adapter as the source of the problem .. since the notebook seems to be working fine always for not less than 2 months from date of servicing...

Can a faulty adapter "slowly" damage the power section of a motherboard with time and usage until one fine day the laptop turns out to be dead..?

An yes to the above question with atleast 90% confidence - and i'm done debating.

Appreciate your reply.. but request you to pls understand my point of view .. you said it is "not" doing it slowly.
What I am trying to do here is to narrow down the cause of these "Repeated power section failures on the motherboard" to the adapter itself.
Now, question is whenever I have my motherboard re-worked with this similar fault..it works fine for exactly 2-3 months and I get the motherboard fault -> namely... failure of an IC on the power section.. (This time it is 3 resistors + an IC)

That is why I asked.. whether faulty adapter can 'with time' make a mobo faulty?

thanks for your patience !

Both the motherboards that I have used were faulty ? gosh . . i need to be the man with the least luck on the globe ...!

Anyways, I have been told by the guy that the adapter was 'ok'. So, going ahead with the 35 $ re-work + 11 $ belkin surge protector.

Sincerely hope this resolves my problem for good.