black screen naomi2 but gmz working!!WHERE R VIDEO IC ON MB

OldFoo · Post by **OldFoo** » Wed Jun 18, 2008 9:58 pm

Hello,

i' ve got a black screen when i turn on my naomi 2. i can listen naomi logo sound and also the game sound running...i can put credit (without see anything) and play game (blind mode)....

all fans are working, tested ones on chip by cutting power the game stop.

i 've to add that when i received this naomi 2 , she was faulty i have changed the connector board (where you plug vga , power) because one line was burned near the connector just above vga plug.

what can be the problem

thanks for your help

OldFoo · Post by **OldFoo** » Wed Jun 18, 2008 10:07 pm

I had a similar problem, but it was rectified by swapping the filetr-board (which from the sounds of things you have done)

Try checking all the boards are connected firmly, and that you have attached your VGA cable correctly.

Also (with power off) try changing DIP1 to see if it's a 15/31K issue

Failing that, how much for the mobo shipped to the UK? I could do with some spare parts :smt006

OldFoo · Post by **OldFoo** » Thu Jun 19, 2008 12:56 am

Try plugging the Mobo into a normal PC monitor. Should quickly be an indicator if there is anything wrong with the mobo.

OldFoo · Post by **OldFoo** » Thu Jun 19, 2008 3:35 pm

ok , thanks, i'll try this tonight....

dj_johnnyg, i hope to make it alive....

OldFoo · Post by **OldFoo** » Thu Jun 19, 2008 11:22 pm

ok not yet tested vga monitor (no one for the moment) but tested connection (vga cable) and nothing occurs.

i've found this topic http://www.sega-naomi.com/forum/viewtop ... ght=jumper

this is the same problem i ve got.

i 've tried to change the filter board : no result

putting a cable on the both point directly on the old filter board has no effect too.

what it can be???

i was wondering about jumper on the nomi2 motherboard itself.perhaps the old owner tried to modify them. what are good postion for them??? or picture of your motherboard will be nice too.

another question: about voltage , i 've got a universal cabinet could be the psu not delivering enough power??? can i regulate it ???

thx

OldFoo · Post by **OldFoo** » Fri Jun 20, 2008 7:19 pm

The test with a vga monitor show that there is a signal because it switch on...

i 've tested a 15khz signal and then the monitor was indicating that the frequency was unsupported.

it's like it miss something in the signal????

As AndyGeezer said me it could be the video ic (where it is located ?????) . i've looked i 've got anything damaged on the pcb, no line burnt....

still need the settings of motherboard jumper settings....

thanks for your help

OldFoo · Post by **OldFoo** » Mon Jun 23, 2008 3:54 pm

Up, help needed

OldFoo · Post by **OldFoo** » Mon Jun 23, 2008 4:00 pm

It is normal that a computer monitor displays an error message when set to 15khz. This mode is not supported by (most) VGA monitors because it is not VGA.

OldFoo · Post by **OldFoo** » Wed Jun 25, 2008 1:24 pm

yes i agree.

it made a test with a 31khz signal and th e monitor switch on too but still no image.

it was just for telling that there is a signal .... and give more information about my problem.

So what can be the diagnostic ????

OldFoo · Post by **OldFoo** » Sat Jun 28, 2008 5:07 pm

UP ??

No one know where are viedo ic ???

thx