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Showing posts from January, 2011

For Advanced Techs

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Click to Read QRCode After answering questions from average users it appears that things may need to change to better serve techs.  Though previously stated, this is a help site for techs, I have been inundated with questions from users.  Stay tuned.

Toshiba X305 - Powers On, Charge Light but Dead no Video

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(Pic 1) bare motherboard on bench This comes from a cousin via UPS from Indianapolis and promised him I'd take a look at it.  The Toshiba X305 is a nice looking machine but still has the flawed nVidia chip design. Disassembling the unit to be able to work on the motherboard without having to have all the connections was a challenge, but eventually I got the unit to work on the bench. Using the Power Jack and external video, it powered on with external video.  This tells me two things. One the GPU is OK but the video memory is defective or not addressing all the lines of the GPU properly.  Picture 2 with the stripes definitely tells me that it is the video memory! Now attempting to repair this issue is similar to the reflow heat process used on an earlier DV series video issue   (with video) .   Picture 3 shows the second screen attempting to boot from network adapter but the characters are incorrect and pixelated.  Picture 4 shows the video daughterboard.  (Pic

DV7 Dead No Lights, will not charge

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DV 7 Power In Section Getting back to postings. A DV7 was brought in that was totally dead and would not even light the LED on the side power connector.  These units are totally different than the previous DV2xxx, DV6xxx, DV9xxx series, and the power indicator on the side gets power from the board not the charger. So if the power in is good, it will not give you any indication, because it draws 5v from the laptop and not the DC jack circuit board. When checking the system I used a meter and checked the red wire (Line In POS+) and it had the 19v and the yellow was 0v. Moving to the next chip in the circuit I tested the SI4835 mosfet and it was dead shorted in both directions. So I took it out of circuit and tested it on the bench with meter- same thing.  The mosfet was shorted. When it should allow current in one direction only, it was allowing in both directions and the unit would never power on. Without having the exact number available, I went to the manufacturers site (S