Build Your Own Arcade Controls Forum
Main => Main Forum => Topic started by: Midcoastsurf on June 12, 2018, 08:38:49 am
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Hello,
I'm working on a GT Complete and it turns on - marquee lights up, green board LED's flashing (green and red) and I can hear the hard drive turning off and on. If I turn the brightness all the way up on the monitor, it's dark red. I don't see any text. Once in a while I'll get some static from the speakers, but no recognizable voices/music. I tested voltages to the hard drive and on the green board (back of the molex connectors providing power) and I get 5.34vDC and 12.7vDC. From the posts I've read with similar issues, people have pointed to a bad video card.
I hooked up the the VGA port on the video card to a computer monitor, and the monitor power LED just flashes green (doesn't lock solid green as though a signal is received).
How do I determine if this is a hard drive, video card, or other issue?
Thanks
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the board will boot up without a hard drive attached (to a certain extent). remove the harddrive and power it up...it should display text saying it's searching for a drive. if you don't get that, you have issues in the board.
try removing and reseating the video card. it's a pain to do (all kinds of finicky bolts), but sometimes that fixes it.
otherwise double check your power... 5 volts should be somewhere around 5.0 to 5.3 never lower than 5 though.
also check your 5 volts on AC measuring... this will give you an idea of the ripple on the line. if it's over than about 40mv AC voltage you probably need replace the power supply as it's putting in too much noise. you are going to want to do this while it's powering the board.
if it still refuses to output a video signal it might be the videocard...but i wouldn't throw the hat in on it quite yet.
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lilshawn - thanks for the info!
What are the optimal voltages for the +12vDC? A little above 12? Maybe 12.1-12.3? I'm measuring 5.34 at the hard drive and at the green board but around 12.7 for the +12 areas on the board.
I have another boardset w/ video card coming this week which should help with the troubleshooting. In the meantime, I'll try disconnecting the hard drive and see if I get any text on the screen.
Thanks!
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the 12 volt is typically unregulated and just sort of follows the 5 volt line (which is regulated.) it will often float around depending on the load on 5v
12v could be anywhere from 11.5 to 13 and still be "good". I think ATX standard allows the 12v to be 11.4 V to +12.6 and be "in spec" typically the 12v gets used for things like the motor on the harddrive and the audio amps. it can also be regulated down to other voltages (3.3 or maybe 1.2), but even then, it doesn't really matter.
really the important one is the 5 volt. it has to be good and solid or things don't work right.
the red boards where a little more forgiving... and a littel easier to power, being they they use a regular old ATX power supply.
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the board will boot up without a hard drive attached (to a certain extent). remove the harddrive and power it up...it should display text saying it's searching for a drive. if you don't get that, you have issues in the board.
Good call! With the hard drive disconnected, I now get text on the screen saying that it's detecting IDE hard drive and starts counting up. If I hold down the start button when I power on the game I can get into the diagnostics screen and all tests pass except the hard drive.
What's the best/cheapest source for a compact flash drive for GT Complete? eBay?
I'll provide an update once I get a CF card in the game.
Thanks!
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E-bay may be the easiest source. It's going to be a pretty straight forward swap.
It's probably a good idea to get one of those flash drives...many of the IT games drives for sale on ebay are old used units...while guaranteed to work with any bootrom, they are old as dirt and have thousands of hours on them.
speaking of which, be sure to get a bootrom and drive combo if your current Eagle boot rom is less than version 2.09. otherwise you will have boot issues. it should say on the chip itself (or the boot screen) what the version is.