VS2 Junkie
Newbie
- Credits
- 28CR
Just after fixing Daytona U.S.A. my Virtua Striker 2 v98 decided to pack up
.
I was faced with 2 faults.
1. the polygons where all screwed up.
2. the ram backup was bad.
Note the game always has 99 credits(even after resetting the game from the test menu)
Going into test mode the machine showed the faults.
and the videoboard
So the first job was to fix the CPU board.
First i changed the 2 static ram chips.
Easy right !!!!!!
Well no
when i fitted the board back in the machine i still had a test fail of IC21-IC22 so i had to dig a bit deeper.
Next i replaced the supercap and the coincell.
after replacing i tested again and still no joy on the ram chip fault.
I checked the select lines with a scope on bootup and all seemed fine except the Pin 20(CS1) which is partly tied to the ram battery controller (MB3780A).
So metering from pin 9(reset) of the MB3780A to pin 20 of the static rams i found that they where open circuit.
As can be seen in the pics there is corrosion around the last empty slot for a static ram IC and i think this has been caused by a fan in the model 3 cabinet that sits directly below the CPU cage blowing damp air at the cage itself.I rectified this by turning the fan round to draw air away from the cage but still giving airflow.
PCB faulty track.
Fan mod.
Next i used a USB microscope to find the exact location of the fault.
Below is the microscope view of the red square.
Next is the track repair.
On putting the board back in the machine i got......
That's one of the two faults done.
The next part was to replace IC83 & ICIC84 on the videoboard.
and cleaned up.
And yes i did get that small spot of solder off IC83
Replacement chips done.
CPU back in.
All done and working 100%.
As my username will tell you this is my addiction and i also have it on the dreamcast.
This game has to be working at all costs
I have another model3 CPU card and videoboard to have a go at in the future.
I was faced with 2 faults.
1. the polygons where all screwed up.
2. the ram backup was bad.
Note the game always has 99 credits(even after resetting the game from the test menu)
Going into test mode the machine showed the faults.
and the videoboard
So the first job was to fix the CPU board.
First i changed the 2 static ram chips.
Easy right !!!!!!
Well no
when i fitted the board back in the machine i still had a test fail of IC21-IC22 so i had to dig a bit deeper.
Next i replaced the supercap and the coincell.
after replacing i tested again and still no joy on the ram chip fault.
I checked the select lines with a scope on bootup and all seemed fine except the Pin 20(CS1) which is partly tied to the ram battery controller (MB3780A).
So metering from pin 9(reset) of the MB3780A to pin 20 of the static rams i found that they where open circuit.
As can be seen in the pics there is corrosion around the last empty slot for a static ram IC and i think this has been caused by a fan in the model 3 cabinet that sits directly below the CPU cage blowing damp air at the cage itself.I rectified this by turning the fan round to draw air away from the cage but still giving airflow.
PCB faulty track.
Fan mod.
Next i used a USB microscope to find the exact location of the fault.
Below is the microscope view of the red square.
Next is the track repair.
On putting the board back in the machine i got......
That's one of the two faults done.
The next part was to replace IC83 & ICIC84 on the videoboard.
and cleaned up.
And yes i did get that small spot of solder off IC83
Replacement chips done.
CPU back in.
All done and working 100%.
As my username will tell you this is my addiction and i also have it on the dreamcast.
This game has to be working at all costs
I have another model3 CPU card and videoboard to have a go at in the future.
