New discoveries for Gamecube Motherboard

Tchay

Tchay

Frequent Poster
EDIT: segments are not necessary, totally overkill :p


Zenloc, I woulda PM'd you this but I didn't want it to get lost in the abyss of PMs :p

Ironically, trimming the motherboard even further than before gets rid of the sound all over again. Only this time, my nifty sound relocation doesn't work. The problem lies in missing components (due to the trimming).


ghipj.jpg


These 3 highlighted components are not only an issue, but behave inconsistently. The RED components are not even present on certain motherboards. Other motherboards have all of these components. From my experience, if the board has ALL of the spots filled in, then removing a single one will get rid of sound AND cause your memory card slot A to get an error.

BLUE - this is the odd part. If your board doesnt come with the red components, then you can just scratch off the blue one no problems. HOWEVER, I began cutting the motherboard and then, without reason, the sound went away, and the memory card no longer read properly. Here's what I cut:


The blue line shows where I cut at first. I relocated as necessary with my "segmentation" method, tested it, everything worked fine. Then I got ambitious :facepalm: and recut along the red line. Such a slight difference, yet this caused sound to not work and the memory card to not read. I spent 3 hours troubleshooting and testing voltages and what not. I honestly can't figure out why the missing components would be a problem NOW as appose to in the very beginning when I ripped them off (and nothing bad happened). And no, it was not a voltage problem. ALL the correct voltages were being distributed to the right places (Heck, theres only 2 voltages to manage in this area so its pretty basic).
cbjCt.jpg


If any of you have a board that doesn't have the top red and the blue, PM me :) because that is the line I want to cut along.

Anyways, I am going to see if I can use another segment from another board with the components in place to get my broken motherboard working (it still plays games, but no sound or memory card). I would solder from a board segment (that has the components) to my broken board with the missing components. Match the traces and hope latency and thin wiring isn't an issue.

ALSO, sound runs off 5v. Memory card runs of 5v (and 3.3v). I don't think its a coincidence that both stop working when you mess around with these little DA components. Oh and if anyone has any idea what the components actually do, that would be great. Maybe show a datasheet or something?

ZENLOC - have you come across any of this? I could sure use some help on this one...
 
I don't know anything about said issue, but I want to ask you about running the sound off of 5v.
Have you come across boards that have epicfail sound quality at 5v? But they do fine at 7.2v(unless it gets loud)? And even then perfect at 12v?

Have you been able to make any distinction as to what revs are picky or not?

SS
 
ShockSlayer said:
I don't know anything about said issue, but I want to ask you about running the sound off of 5v.
Have you come across boards that have epicfail sound quality at 5v? But they do fine at 7.2v(unless it gets loud)? And even then perfect at 12v?

Have you been able to make any distinction as to what revs are picky or not?

SS
Click to expand...


Not yet, BUT I have noticed that trimming along the AV side too close to the NEC chip (sound chip I believe), can cause crappy sound quality for SOME boards. I have yet to figure out the differences. There are even different types of Rev A boards (as well as different revision B boards). I have like 15 motherboards, so Im going to try to find some categories for them.

Zenloc also said some boards get picky running on really low voltages (with his custom regulator).

EDIT - You just gave me an idea though. I'm going to unbridge the 5v and 12v lines. Then I will feed in 12v to the right spots and see if this gets the sound back and the memory card working. I guess it cant hurt to try it.
 
Ah good to see that you tried some more trimming. I have also done the same. And come to the following conclusions.

The parts you are referring to have nothing to do with audio. All those little chip like things are used for the controller data line and memorycard data lines.

As for the sound. I have made a discovery that will make the sound amp on the board obsolete. This also works for the n64. The DAC chip on the n64 gives you video and audio signals. That then get's sent to the audio amp. But if you are using an external audio amp already that has proper speaker output just take off all the audio amp components and wire it directly to the DAC chip. This works exactly the same for the gamecube.

So we don't even need it. Just get rid of all surrounding components that are used and wire the sound directly to the DAC chip.

Also the 3.3v and 5v lines are used for the memorycards. These need to be present when rewiring a memorycard slot or card built-in. The components you highlighted are only for DATA!! just to make things clear. 5v is also used for the disc drive motor but we already knew that.

I already have a correctly working board that is cut in my GameCubeSlide. Everything works perfect!! All controllers, memorycard slots and disc drive.

Like you are trying it can be made even smaller. But you would have to rewire all those little chips and move allot of surrounding components to make it work. The question is is it worth all that effort just to cut is a little smaller. I mean the disc drive and battery's make it big already.

But yeah I still like the fact that you can trim it down super small just to prove it works!! :twisted:

I'll post some pics in a couple of days. Gonna be out for the weekend.
 
Alright! WOW. This is awesome information!!!!!!!!!!!!!!! And yeah, I am a maniac at cutting motherboards so I always want it just a little bit smaller :pirate:

First off, I'm not sure which chip on the mobo is the DAC chip. Are you talking about the AMP-DOL chip (backside of board near AV)????

And that is great that we can replace the amp. Might solve SS's problem :D

Normally I would want to cut out more on the AV side BUT I want to use VGA for my next portable so I am limited by the 3 small FIL chips (same as the 4 chips outputing to the DD). I am not sure what the chips do, but I would be afraid to relocate them....

Now, for the memory card/controller area, I was only planning on cutting out those first two little components (seen in the above picture). Whats weird is that I removed the blue on another board, and both the memory card and controller work fine. I'll have to see what ends up causing an issue. When you cut that far back, the wiring actually gets easier in a way. I only need 5 wires for voltage (and we only have 5v and 3.43v to relocate) so the process actually ends up being easier than you standard DD relocation. At least in my opinion :D

EDIT: I also use my "segment" method for these relocations. I cut a segment of an old mobo and bring it to life by feeding voltages back into and then wiring from my working mobo to this segment to use its tiny components. That makes the relocation process much easier. I've tested the method and it does work.


Thanks for the help Zenloc!!! That definitely clears up a lot of confusion.
 
Nice, I hadn't mentioned it but the thought of replacing the onboard amp has crossed my mind. Chalk one more up for the "Things on the gamecube that need replacing" list.

Now I want to go and design a PCB for the GC with the reg's and amp on it. Also, tchay, for those small components you might save money by desoldering them with a hot air pen and a pair of tweezers. Maybe you could ruin less mobo's that way. :lol:

SS
 
ShockSlayer said:
Nice, I hadn't mentioned it but the thought of replacing the onboard amp has crossed my mind. Chalk one more up for the "Things on the gamecube that need replacing" list.

Now I want to go and design a PCB for the GC with the reg's and amp on it. Also, tchay, for those small components you might save money by desoldering them with a hot air pen and a pair of tweezers. Maybe you could ruin less mobo's that way. :lol:

SS
Click to expand...

Yeah.....jesus.....
 
To Tchay: I'm talking about the av chip above the digital port. The amp-dol is the sou amp which you can get rid of. Those fill chips (just like when they are connected) are nothing but filtering caps. You can remove them and wire directly to the spot is connects to.

I see those fill caps like everywhere. For data controller line, 3,3v and 5v memorycard line, 5v disc drive line, disc drive data lines, digital out and many more. But I removed them and it worked fine. Guess it's a game of test and see what it does.

To SS: I wouldn't even bother with a new PCB. Far to much work and too complex. Just cut it as small as possible then just connect the audio and video lines to a screen with sound amp like the psone screen and your done. Nothing else needed.
 
What I don't get is, if the gamecube already has a sound amp on the board, why do we always have to have another sound amp to get audio out of the gamecube? Why can't we just wire 2 speakers directly to the mobo???
 
Because it's not a requirement in the intended design. Remember, gamecubes are supposed to be plugged into a TV, which has it's own amp.

Although technically you can, I've tried it. It's rather quiet. I think it's okay w/headphones, but I don't remember. XD

SS
 
Jep that about sums it up. The amp built-in the gamecube and n64 aswell is a pre amp. Give it a clean and powerful signal to the tv so the amp in tere can do it's work.
 
Interesting. I never knew that.

As a side note, I did some "Benheck" testing last night and so far at least 5 of the big caps are needed for the gamecube to run properly on a Rev A/B NTSC board. (might be less picky on PAL, not sure).

The gamecube motherboard seems SO simple now :dah:

Why the Heck didn't we do this hidden layer stuff a year ago, woulda saved me loads of motherboards :lol:
 
Weird... it doesn't needs so many caps. The gamecubeslide I'm making has a ntsc gamecube slimmed down with only one small cap. All the others I took off as they were all being used by the sound amp.

The layer scans were the breakthrough point for me though. When I was able to see where everything went it, making things smaller and working correctly suddenly was a piece of cake.

They one and only downside it the laser assembly.

There is a option I think which might make it much thinner. Altough I'm not sure.

the panasonic gamecube only released in japan has a dvd player built-in. I wonder what the gamcube laser looks like in there. I'm looking to get one but the're so expensive!

If you find one for a good price let me know. I'm wiling to lay down some cash to find out something revolutionary...
 
I looked into the P-Cube a while back and I'm pretty sure the Disc drive is the same. I think what is different is the daughter board.

Now, emu_kidid has reassured me that the compatibility on his DD-replacing hard drive will be good. He even said audio and speeds would be at sufficient levels. Lets hope. I've had enough of the god dang disc drive :p
 
Tchay said:
I looked into the P-Cube a while back and I'm pretty sure the Disc drive is the same.
Click to expand...
I did the exact same thing a long time a go. Turns out it used 2 lasers. One for the dvd and one for the gamecube disks.
 
You must log in or register to reply here.

Similar threads

M
Internal game saving mod
Replies
1
Views
381
ttsgeb
ttsgeb
robm
robm's GamePi XL Build (3d-printed rPi-based 7" touchscreen handheld emulator)
Replies
5
Views
483
robm
robm
M
Scaling SFC to UK HD TV.
Replies
2
Views
171
meowwentthedinosaur
M
C
Weird Acting Second Hand N64. Is It Moded?
Replies
1
Views
661
ttsgeb
ttsgeb
buddygz
help with GDEMU/Dreamcast handheld
Replies
1
Views
2K
ttsgeb
ttsgeb
Back
Top