IBM 6736-hc9 bad DVI input

[neisg1]

I first thought this was bad power supply caps but the power board tests OK. When connected to the DVI input the video is jumpy and noisy. However when connected to the VGA input it works fine.

[neisg1]

Re: IBM 6736-hc9 bad DVI input

Update, When turned on cold the image is jumpy on both DVI and VGA once warmed up for 30 min or so it seems to work ok. Tested all the power supply caps for ESR and they all look Ok.

[piernov]

Re: IBM 6736-hc9 bad DVI input

Check the capacitors on the motherboard.

[neisg1]

Re: IBM 6736-hc9 bad DVI input

OK Thanks,
I already checked that caps on the power board and all were good. I am now looking at the main Video/motherboard and have found a couple of caps with high ESR. Not sure if I have replacements on hand. Will post back later.

[neisg1]

Re: IBM 6736-hc9 bad DVI input

The 2 larger 470uf caps on the main video board test high ESR, I have an order for these in shipping.

[neisg1]

Re: IBM 6736-hc9 bad DVI input (SOLVED)

As the problem disappeared when the monitor warms up, I used freeze spray to cool the suspect capacitors. when capacitor capacitor C220 see image was cooled the problem returned and as it rewarmed the problem once again disappeared.

Thanks for the input guys.

[neisg1]

Re: IBM 6736-hc9 bad DVI input

Replaced the 2-470uf caps and all is good now