HP 6735b - no post and Caps Lock, Num Lock blinking 5 times

[AngryBuddha]

I'm nearly at my wit's end.  Laptop failed to boot a few weeks ago.  Blank screen, flashing LEDs x5, HDD light blinking amber (with or without drive installed).  I've since swapped out the system board (same error code), and recently the processor (and still same error code). 

Every Internet search turns up nothing useful (BIOS resets, voodoo chants, etc.).  Has anyone solved this issue?  I don't want to Easter Egg my way into a fix even though i've already started on that path.

Should I just consider this thing a brick?  I see a lot of folks with the same issue, but zero solutions.

Any insight would be greatly appreciated!

[Mumbodog]

Did you try a different AC adapter yet?

[henniware]

i tried the lc power lc120nb (www.lc-power.com) without success ! read more :

A customer brought it to me yesterday as it no longer started. the caps and num led blinked five times. It has previously been a few times no longer start. the second start worked every time, until the day before yesterday.
I've removed everything (dvd, hdd, bluetooth, wifi, ram, cmos-battery). the laptop would not start. Next, I still took out the cpu and the heat pipe and fan. after the start it showes the same fault as before. I cleaned the heat pipe and put the cpu, heatpipe and fan back. suddenly it showed another error. I think the leds blinked thrice. i guess ram was dismissed.

I built it all back and it gets started again, but exactly every second time. I've made ​​about 40 starts of which 20 were successful. I was surprised. when I removed the battery, the laptop started not more. also not every second time. I suspected a faulty power supply and exchanged it for a universal power supply with the same performance. without success. The notebook starts after 6 hours still with the battery and the original power supply. after 12 additional hours,
the laptop started no more.

I suspect the voltage converters on the motherboard is defective and does not provide enough power anymore.

it's bad that there is no exact documentation of the error of the blinking leds. "The mainboard is defectiv" can mean anything.

[DuaneWong]

I, recently, bought a 6735b hp laptop for $100. It does the same thing as your describe. I think the motherboard overheated. So, I ordered a new motherboard from getcomputerparts.com out of China to see if it will solve the no boot problem. I'm hoping this will solve the problem. I noticed that when I first got the laptop, second hand, that the fan wasn't blowing out, and later found a lot of dust that simply blowing it out solved the air circulation problem. I think that the heat destroyed some connections to the video or hard disk drive controller chip which made my hdd light blink on and off every second or so, and also made my Optical Drive seem to blink its LED on and off, and a slight scratching sound every second, as well.

I also, saw on Youtube.com, a video about the nvidia video chip getting connection heat damage at the solder joints, and there was a way of putting a penny with heat sink paste after 'burning' it for a couple of hours with a hot spotlight lamp with aluminum foil around the rest of the board to protect the rest of the board other than the video chip. But, this was on another hp product that failed after 1 year, no screen no POST.

I am hoping a 'new' system board will do the trick though, and I am spending about $153 for the part delivered, and $75 to put it in at a local computer shop.

part url:

http://www.getcomputerparts.com/hp-compaq-6535b-6735b-series-laptop-motherboard-system-board48819400...

Wish me luck!

-Duane

[DuaneWong]

I wonder, if you change the motherboard with a new one, would the ' voltage converters' on the board that you suspect is bad, come with the new motherboard (system board)?

I,also, had a problem with the BIOS not letting me in to change settings and requiring a password, which I did not know.

I understand that a chip can be replaced that is soldered in, that can remove the password for about $35 on Ebay.com for this computer. But, that can be tricky.

I, also, decided to get a new motherboard that wasn't refurbished or remanufactured, or used, so that I would have no password on the BIOS. I hope getting a 'new' motherboard works for me.

http://www.getcomputerparts.com/hp-compaq-6535b-6735b-series-laptop-motherboard-system-board48819400...

-Duane

[DuaneWong]

Would new 'voltage converters' come with a new system board?

[DuaneWong]

http://computerszine.com/baking-the-motherboard-hp-pavilion-dv2500-nvidia-video-chip-fix-no-video-co...

Baking the motherboard attempt to get nvidia chip to work again, due to solder connections being compromised by heat and lack of pressure from the heat sink, or something like that.

[Nicker321]

I have the same error, and I too bought a new one from getcomputerparts...the same error, 5 times blinking.

Has anybody fixed this error?

greetings from Germany

[DuaneWong]

Are you sure that you got a 'new' motherboard and not a used one? I am waiting for my 'new' unused unrefurbished motherboard to come in the mail for the tech to install.

How much did you pay, and when did you buy it? What motherboard number was it that you bought from GetComputerParts.com? Or was it another company?

-Duane

[Nicker321]

Hi Duane,

no I think it`a used but refurbished motherboard, and I bought it vom getcomputerparts in China. the number printed on a sticker is IEC s/n JJ8AMC07U3, SPS: 488194, TT 2.0 FF System board, AS# Rev. 2.0, CT: PAKKV00RRHY82PM and a date code 9508A4.

I have payed 88 EUR for this motherboard (115 US $) plus shipment and I bought it end of september, my exchange board came a few days ago. 

Yesterday I have got a mail from them:

I was there tested the board together with my engineer.

As it is the replacement board, we tested it very strictly

could you please let me know more details

cpu processor working?

best regards