Original Xbox fail clock capacitor replacement

If you tell me that it's normal the charge only last for less than a day, then I am fine with It. So everything seems ok! Then I pretty about the overall result!

But what's the point of making a system that its clock only lasts for less than a day if left unplugged. It's supposed to last for long, not less than day, at least when compared to other systems.

Thanks guys

 

It was probably just used to keep the time in case of a power outage. I assume they figure people were going to keep it hooked up to power at all times.

 

It has no battery like other systems, so yep.. they expected everyone to keep their systems plugged in.

 

Remove that capacitor, use NTP (XBMC installed as Dashboard can do that for you) to setup day/time. I do that on my XBOX. It NEVER has wrong time and there's 0% of chance of leaking.

 

What about solid state caps

 

I have repaired at least two other xbox after trying to repair mine and I am the only one to blame. The other two are working perfectly and they retain their charge. Do you guys have any schematic which could help me repairing the trace that I had absolutely destroyed? I am not really a big fan of modchipping my stuff.

 

What board revision do you have?

 

Version 1.0

 

You could measure the capacitor voltage and see how fast it goes away when the system is unplugged.

The goldcap backup was only needed when the power was unplugged. That's why they thought that keeping it going for a day was fine.

They probably used a bad quality goldcap. If you buy another one with the same spec's, it will likely be bigger.

A 3V coin cell with a diode should work as well.
I see no reason why the xbox would drain that battery real fast.
The diode should give a voltage drop of 0.4 - 0.7V, leaving 2.3 - 2.6V on the circuit.
You could check the datasheets of the clockchip to figure out from what voltage it goes into low power mode.
The capacitor is 1 farad, so no, you can't use solid state capacitors. Only goldcap's go that high.
A pc mobo can retain it's bios and clock settings for several years on a 3V coin cell. The same should be possible with the xbox as well.
Another alternative to the goldcap that was often used is a rechargable battery. Guess what, after some years those started to leak as well.

The spilled liquid from the original goldcap is not only corrosive, it's conductive as well. It could cause som extra current draining the goldcap faster. If you cleaned it properly, it might indeed be a pcb track that is corroded away. My guess is that the goldcap isn't getting charged when the xbox is powered.

 

The reason why the battery is drained too fast is the production technology of the southbridge chip.

It has been stated somewhere that the original plan was to have real batteries to keep the clock but that was proven to be not economical due to the leakage being too much for backup purposes. Repairing that or having the RTC outside the southbridge would raise costs (redesign the chip, motherboard and maybe add parts) and very likely delay the project beyond the release deadline... They also had issues with the southbridge USB ports. The HUB board on the early units is a "hot fix" for that.

On the 360 they did not take risks and went with the NTP route I suggested a few posts ago. The console syncs the clock with XBOX Live on power up through the network port even without a profile being logged in. That way it can keep right date/time on the files stored on the flash memory (kernel) and harddrive (dashboard extras).

 

After looking closely, it seems that I have damaged the traces for this specific capacitor. I am interested in finding alternative traces for soldering the capacitor. I am not a big fan of modding, I like keeping my stuff as the retail version.

 

Out of interest does the 1.6 board (crystal xbox) also have this cap in it?

If so I'll just remove the damn thing and be done with it.

 

It does. It's near the IDE/ATA connector, the golden one which is mounted with long terminals. (they started to mount it with long leads haha)

 

Careful, I've read that unlike 1.0-1.5 Xbox's, the 1.6 won't run without that cap (maybe someone will chime in and confirm or not). V1.6 uses a different brand of supercap anyways and I haven't had any issues with them personally, and the ones I've dealt with still kept the time.

My rule of thumb for Xbox's has been:
1.6: leave it
1.0-1.5: remove it, even if it looks OK.

 

Cheers for the advice I'll leave it for now and see how it goes, hasn't been used much in the last 5 years however so right now I have to keep it plugged in if I want it to keep time.