Medion P6618 - display won't start

[yohnsee]

Hello everyone,
I need a little help. I bought this machine cheap and I want to repair it. But I am stuck so came here for a little help.
Long story short: it came without CPU and memory. Original CPU must have been T6600, I only have T4200 in my bin (this will be important later).
First I tried to power it on, it draw 600mA@19V from my power supply, but had no picture. I started to measure the voltages, and found that CPU VCC_Core was not present. There was a nasty short after U40 on the 1D1V line. I tried to find it by applying 1V@3A and see what gets hot. But after a few seconds the short was gone, and I saw no smoke and felt warm nowhere. Then I fired the motherboard up, and now it draws 1.6A@19V, all the voltage rails are present, but I still have no picture, no backlight, nothing. I desoldered the Eprom (U41, W25X16AV) read out the contents 3 times, they are the same. Downloaded the latest (?) bin from the manufacturer, wrote it in the chip, but still won't start.
I found out, that U24 switches the LCD voltage, it should receive a signal on PIN3 from the GPU, but it isn't happening. Do you have any ideas? I attach the schematics, maybe someone has time for it.

Thanks in advance.

Edit: T4200 has 800MHz FSB, if I put in anything else in the CPU socket, the machine resets itself about every 5 seconds.

[diif]

Re: Medion P6618 - display won't start

Where did you get the bin file ? I only see updates on the Medion website.

How did you measure the short ?

[yohnsee]

Re: Medion P6618 - display won't start

Where did you get the bin file ? I only see updates on the Medion website.

How did you measure the short ?

Hello, thank you for your message.
I downloaded this: Link
After extracting it has an exe file in it, I opened it with hex editor, searched for the first matching hex group (5 exactly) with the old one I read from the eprom. Then cut away the beginning of file, calculated to 2kbytes and cut away the rest of the file. The rest was compared with the original, the only difference is that in the original there is a part where you can see a lot FF, in the new it is 00.
But as I said, tried both, outcome is the same.
I measured the short with multimeter. It showed 0.68 Ohms to ground (my probes show ~0.19 Ohms when they are shorted to each other)

[yohnsee]

Re: Medion P6618 - display won't start

Have I done something wrong?
Or am I on the wrong track with this?