Replacing the DC PSU

No, I'm in the US. I want to say it was a little over $5 for shipping.

 

I used the 80w. http://www.mini-box.com/picoPSU-80

 

Thank you

 

The DC draws less than 40W wihtout the gd-rom drive, so you should know that 80W is overkill. That said, I used a 120W one because it's the one I had.

 

Can I assume these run much cooler than the stock DC PSU?

 

Yes.

 

Would you happen to know how much it draws with the Gdrom?

 

No sorry, but the DC is rated for low wattage IIRC, 27W or so?

From memory it's rated around 27W and draws 16W or so with gd-emu.

 

For those who are interested, here is my finished power supply mod.






I used a molex connector for the power switch, it will be easier if I ever need to replace the wiring harness. I can just add the connector to the new harness instead of desoldering the switch. I managed to fit the power in into the one from the original power supply, no modding of the case necessary and it looks somewhat original. I think I'm done messing with this Dreamcast for right now.


and here's two pictures of it all put back together...






It's amazing how light the dreamcast is without the GDROM and PSU.

 

That's beautifully neat! I want this in mine, like now.

 

That really looks great. I'll be doing this

 

Been meaning to do this mod to my GDemu equipped Dreamcast for ages - these pictures are really really tempting me.

Very neat install

 

Efficiency is shot to shit for most power supplies unless they're having >60% of max load being drawn. It varies from supply to supply but I wonder how the life of the supply is affected by low loads.

Suppose this only really matters if you're into that sort of thing. The wattage is low and you're probably wasting more power running Netflix while you're asleep than this would.

 

AFAIK the picoPSU is still over 80% efficient under low load (I think it's 85% at 1A on both %v and 3.3v rails). Anyways, worst case scenario is 27Watts/0.8 = 33.75 Watts drawn instead of 27, could be worse. As long as the picoPSU doesn't wear too fast, but I think it's fine.

 

I too have put an 80w PicoPSU in my Dreamcast but now that by GDEMU has arrived i'm having a problem with the 12v line having power (roughly 4,5v) when the console is powered off.
When plugging in a controller the VMU will beep and the LED on my VGA box stays lit.

My install can be seen here, it's a bit messy but there are no short circuits. http://f.cl.ly/items/04340L12103G121j1K16/IMG_20150430_123233.jpg
The power switch is wired to PS_ON and the neighboring ground pin.
12v uses pin #10; 5v pin #4; 3v3 is on pin #1.

When unplugging the PSU it disappears and only reappears until after you turn the console on, then off again.
Plugging in the external brick when the console is off leaves the 12v line turned completely off.

Anyone got an idea?

PS: roughly 2,5v remain on the 5v rail, roughly 1v on the 3,3v rail after the console is turned off.


Update: Looks like it's residual charg in the Capacitors, i can soak it by keeping the multimeter probes on it (under 4v the LED and VMU beeps stop) but it won't decay on it's own within a reasonable timeframe.

 

Try disconnecting the blue capacitor on the Dreamcast power switch

 

I had completely forgotten that being there, doesn't make a difference though still the same behavior.

Maybe i should just switch the 12v input instead of using PS_ON...

 

does this happen also if you having the pico disconnected from the Dreamcast?

 

It does. What bugs me is that the voltage immediately drops once i unplug the power brick.
This is a genuine 80watt picoPSU as well, not a cheap copy. Power brick is a 12v 3,7A Wii power supply, genuine as well.
Spot on 3,3; 5 and 12v when turned on.

I will just migrate the switch to the 12v input tomorrow and permanently connect PS_ON to ground, that will probably be my best bet.
Do i splice the switch into the positive or negative wire though, i feel like i should know this...

Anyhow, thanks for helping.

 

one final thought is grounding in general and try different wall plug and make sure that the ground has no current also try another power supply to identify if this is a pico behavior