Hp touchsmart 300 black screen

[crdz66]

Hello friends.

I need you assistance with this computer.

So far.
The computer boot right.
The 2 fans working good.
But the screen remain black.

Checked.
I remove - re-connect the bios battery, hard drive, memory and still can get picture.
When i get this computer i noticed the fans was with plenty dirt even the heatsink.
I think this computer was overheating.
I check the processor and video chip and after 15 seconds feels like are working because generate heat on the top.

I remove the memory and as soon the computer turn on, can't hear beep coming the pc, so, do you think the motherboard is bad???

I check the voltage with to the led connector and show 3.2v

any ideas??

[Life Goes On]

Re: Hp touchsmart 300 black screen

I dont think s the chip but you can reflow it and see, but first try to flash the bios, it could be some bios issue.

[razor_amd]

Re: Hp touchsmart 300 black screen

Is caps lock blinking? How many times before it makes a longer pause?

[crdz66]

Re: Hp touchsmart 300 black screen

I did the reflow.
Can i try twice (the reflow) ?

How can i flash the bios?
Thanks

[passete]

Re: Hp touchsmart 300 black screen

I did the reflow.
Can i try twice (the reflow) ?

How can i flash the bios?
Thanks

With a Bios programmer .
You need to desolder the Bios ic put on programmer, read (backup), erase and flash, then resolder back

[crdz66]

Re: Hp touchsmart 300 black screen

Update.
You guys recommend to buy a new motherboard or can be something wrong with the screen?
Thanks

[crdz66]

Re: Hp touchsmart 300 black screen

I check another things
checked the inverter board and I get 12v on v_in connectors means good. (from motherboard)
fuse is ok. (on inverter board)
how can I check the voltages after the transformers if that ones are working good?
ac on multimeter show me .182v on 4 tracks after the transformers.
is that ok?

[LatinMcG]

Re: Hp touchsmart 300 black screen

I check another things

i could test your bios.. if you get a spi programmer there is some pins for SPI header connection to read bios.

read 2 copies and compare in Hxd Hex editor.
post the file here and i burn to a pc im working on and if it works then we know its not bios..
then again you probably wont see this for days.