Dreamcast synchronism problem? - VGA and SD Mod

Hi all!
Well, I did a VGA Mod, perfectly and worked for several days without problems, but I decided to make the sd card mod and probably I did something wrong, the image doesn't show up more in vga or composite.
I removed the sd card mod, but now the image keep scoming up non-stop, so something must have done wrong in the SD mod, what might have been and how to solve this problem?
I damaged image synchronism of the Dreamcast?

Note: The image now no longer appears in the VGA, composite only.

Below is a video that I made that shows clearly the problem.

<span id="Dst[0][32:40:34:41]" _mstsrc="0_32:40" _mstdst="0_34:41" class="" style="color: rgb(0, 0, 0); font-family: Arial; font-size: 12px; white-space: pre-wrap;">


Thanks!

 

If I understand you properly VGA no longer works but the video above is what you see in composite mode? My money is on RGB and VGA pins being badly grounded. If they aren't being grounded separately I'd give that a shot.

 

Thanks APE, that's right, no more VGA signal and the video above is the composite cable. I'll check and revise the entire circuit, then come back here to show the result.

 

Can I use any GND? How do you know which GNDs not in use in the Dreamcast Board?
Can I use the GND of the Dreamcast power supply? I was using all three pins.


Remembering, the problem only occurred after doing the SD card mod.


Now I will continue to check the connections...

 

Vga mod reviewed, all connections ok and made correctly.
I think I broken the v-sync, which caused the problem as you can see in the video, and also makes the image not be generated in VGA.

Probably I burned some component responsible for plate V-Sync, how do I fix this problem?

I found the video schema in this topic:
http://www.assemblergames.com/forum...0-mainboard-and-power-supply-schematics-scans

I don't know if it will help, but I'm going to use this link to assist me, my knowledge in electronics is still very limited.
yam.20to4.net/dreamcast/va1.html

Thank you, and if anyone has any more information I ask you to please help me, this is not my Dreamcast.