renanbianchi

Hey guys, i came around these pics of a modchip on an old xbox, both sides have wires, a lot of wires on it. And i couldn't figure it out what is happening on this console, it seems to be some kind of reserve bank of the bios? A well known xbox modder said that it was some kind of extended bios bank and that if removed, the console would not turn on. So what do you guys think? This is not a help topic, just information disclosure, as this console is not mine and i'm really curious about this mod.

I've found the problem. The rectifier was good and working perfectly. I've traced it after studying how that MOSFet transistor works. It needs a higher voltage to be turned on, so i traced back to find that there was a 13V source that should go to it, but it was measuring 0.3V only, so the mosfet would never turn on. So I've found the culprit, it was a Shorted zenner diode just behind the mosfet. I've replaced and got it back to work! Thanks for your help, as it convinced me to study how it worked and find the problem.

Hey Dave, thanks for the reply. I did test the motherboard with another psu, so it is working fine. The switches do seem to be working fine, so I'm trying to track what component would be bad. Maybe one of those little black transistors could be the culprit? There isn't any damaged resistor nor diode that I saw. All the caps on the PSU have been properly replaced so they're working fine. Pictures have been attached. As you can see, i've replaced a lot of components on this board lol. But it is working perfectly except the 12v line not turning on.

Hey guys, i' got this 1.6 PSU that seems to be turning the 12v line OFF after some time until it stops feeding it at all. The PSU was burned and repaired by other than me. It seems to be working perfectly, as i made a jumper from the 12v capacitor and it does indeed boot and work for hours, so it must be some component that's responsible for turning off the 12v line on it that is shorted or not operating properly. The thing is, i can't see any damaged component. All the other lines do work and the power button does seem to function. I've been trying to track what component turns off the 12v line when i turn off the console, but to do that i'd need a spare 1.6 PSU which i don't have at the moment. It's a Delta PSU by the way. I've made another post on this forum about the issue but it was in the wrong section. Also i didn't had a clue about what was making the PSU turn off until i found it was the 12v line.

Sorry for taking too long to answer, I've been trying to test some smaller components without success. If you need a video, let me know and I'll show you its behavior. I've tried replacing all the bigger Caps. Also tried to replace the transformer and it indeed is working fine. I have a 220v psu to test along and I'm trying to replace some parts that are identical on both psus to try to find the culprit

Hey guys, I'm trying to find the problem of this Delta psu, it's a us 110v psu. I turn it on, and after some time the console turns off. If I try to turn it on again, it does, but it turns off in a shorter time. It goes like this until it doesn't turn on anymore. If I unplug it and wait some time, it goes back to working until it decides to turn off again. I've checked all caps and all seems to be in working condition. This psu has been repaired before by someone else before I got my hands on it, the fuse has been replaced and the old varistor left some black fumes around it. There isn't any visible damage on the components. Any tips? I just noticed I created the thread in the wrong section. Sorry about that