# Dreamcast PSU Woes



## MrCokeacola (Feb 16, 2020)

Using a GDEMU in a dreamcast and having trouble with the PSU getting hot and having to keep aligning the pins too as they keep going misaligned.

As I'm too cheap to go with the obvious choice a Pico PSU I decided to use some resistors instead pictured below.



 

The thing is the resistors get very hot and one touched the case and even melted it! I've since arranged them better so they don't hit the top of the case but it does seem like things are still getting really really hot.




Should I be afraid of the heat the dreamcast is making or ride it out until the PSU goes kaput then finally mosey up the cash for a Pico? Also any other ideas to keep the system cool?


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## Jokey_Carrot (Feb 16, 2020)

That's an electrical fire waiting to happen.


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## MrCokeacola (Feb 16, 2020)

Jokey_Carrot said:


> That's an electrical fire waiting to happen.


Not really, the resistors and just metal and carbon so if they go nothing will really happen (in theory). Also all they are doing is being connected to the 12V rail (which is used for the disc drive) and feeding that power to ground (so everything is grounded which is also good). Using resistors is recommended when using a GDEMU to reduce heat, but it does not seem to be working. :/


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## subcon959 (Feb 16, 2020)

You could remove the voltage regulator to get rid of the 12V altogether.


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## MrCokeacola (Feb 16, 2020)

subcon959 said:


> You could remove the voltage regulator to get rid of the 12V altogether.


That is an idea, do you happen to know of any tutorials for doing that?


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## subcon959 (Feb 16, 2020)

MrCokeacola said:


> That is an idea, do you happen to know of any tutorials for doing that?


There might be better ones but this came up first https://www.reddit.com/r/dreamcast/comments/461ohk/how_to_remove_12v_from_dreamcast_for_gdemu_and/

This one is good for pics https://imgur.com/gallery/5AtCG

Main thing to note is the placement is different for NTSC or PAL.


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## koffieleut (Feb 16, 2020)

Isn't the 12V for rgb scart? Can't remember that it's for the discdrive. I installed a Pico psu and connected the 12V.


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## Alexander1970 (Feb 16, 2020)

MrCokeacola said:


> Using a GDEMU in a dreamcast and having trouble with the PSU getting hot and having to keep aligning the pins too as they keep going misaligned.
> 
> As I'm too cheap to go with the obvious choice a Pico PSU I decided to use some resistors instead pictured below.
> View attachment 196537
> ...



Hello.

I use the same MOD like you



 

 

but the Resistors getting warm to really warm but not *soo hot*.

Your PSU looks different from mine.
Because of NTSC/PAL Dreamcast ??


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## MrCokeacola (Feb 16, 2020)

alexander1970 said:


> Hello.
> 
> I use the same MOD like you
> 
> ...


Interesting, so after running your Dreamcast for about 45 minutes to an hour your resistors don't get very hot? (I mean I can still touch them but they pretty hot) Also yes the North American Dreamcast has a totally different PSU that has the pins touching the other side.


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## Alexander1970 (Feb 16, 2020)

MrCokeacola said:


> Interesting, so after running your Dreamcast for about 45 minutes to an hour your resistors don't get very hot? (I mean I can still touch them but they pretty hot) Also yes the North American Dreamcast has a totally different PSU that has the pins touching the other side.



Yes I tested it before (about an Hour) and they get a bit more then warm.Not really hot.
The Upper Housing Cover gets also warm on the Spot above where the Resistors are located.

The Air which is blown out from the Fan is warm.Not hot.
The Bottom of the Dreamcast gets also warm.
But not really hot.


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## subcon959 (Feb 17, 2020)

It could also be related to different versions of PSU and different regions (110V or 220V). I have a UK PAL DC (240V) and it doesn't get very hot at all so I didn't even need to use the resistors. I did put a second fan in the back as an intake just because I had a spare one.


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## Alexander1970 (Sep 25, 2020)

Hello.

Thanks to Suggestions from you fellow Dreamcast Fans,I did it today:
Replaced the PSU and "filled" the GD Rom Space with something "Special".


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## MrCokeacola (Sep 25, 2020)

Lookin good Mr. Alex.


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## Alexander1970 (Sep 25, 2020)

MrCokeacola said:


> Lookin good Mr. Alex.


Thank you,my Friend.

And the Best Thing now - really cool Airflow....


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