CPS2 18 in 1 No sound or picture

[mr aize]

Just got one of these boards and there's no sound or picture when powered up on my supergun. (Which works perfectly with my neo geo mv1fz, which is jamma as well) Bit gutted really..... The leds on the board light up, suggesting it's powered up, but that's it. Read somewhere else that it takes a lot of power but surely, if it's jamma, it can only be using 5v and 12v for the sound? Any help gratefully recieved!

[BobA]

Only PS info I have on a real CPS2 board

* The CPS-II will draw appx. 3.5 A from +5 V.

* The CPS-II will draw appx. 0.4 A from +12 V.

18 in 1 is modified so a bit more power is probably needed.

[mr aize]

Thanks, I'm gonna check the voltages being supplied by my atx, perhaps they're a fraction too low. It's quite a big one so should easilly handle the amps.

[mr aize]

Right, i'm fairly certain it's being caused by the voltage dropping too low, I hooked up an old arcade power supply I had and got it up to around 4.5 volts, result, wavy lines and colour on the screen, not exactly a playable image but it's a start . Unfortunately the potentiometer is all the way up and so I can't get it up to the required 5v. Way I see it, i've got 2 options, either mod the arcade supply to output a higher voltage or solder some extra wires to the board to get the required voltage where it's needed. Any ideas where that might be would be much appreciated. Figure that would also be a good way to extend the life of the board and prevent overheating.

[BobA]

If the pot is all the way up on voltage adjustment then you probably will not get any more out of it.   The more red yellow and black wires that are bundled together on an atx supply the more current can be supplied with less voltage drop.   You might also want to make sure your wires are a heavier gauge to provide the higher current required for the PS wiring.