XBOX 360 PC Power Supply Conversion
XBOX 360 Power Supply Replacement
Power Supply requirements
Almost any atx supply would do the job but first make sure the power supply can cope with the load of the 360, which is 12V @ 16A. and 5V @ xxA.
As our customer was in a rush to get the job done (as they all tend to be) we had them source a unit themselves. They ended up getting a TOP-500P5. This supply was capable of supplying 28A @ 12 V and 50A @ 5 V!
This unit should suffice.
Rewiring the power supply to boot without a PC
After a few quick google searches we found a few peeps have been doing a similar thing so we can verify that their information is correct. This was the best diagram we found. The only trick is to short that pin to ground to force the power supply to startup.
Problems Encountered
After wiring the unit we found it would only boot for about one second then shutdown. We double checked all our wiring then started cursing about the mis-informtion superhighway ... we cracked out the multimeters to see what was going on.
Whilst wired correctly the power supply had a fairly decent sized inductor on the 12V rail and the current required during booting wasn't being supplied fast enough (the inductor prevents this from happening) so this is why the unit would boot then shutdown.
The Solution
This was simple. As the unit could deliver easily the required current capacity we just loaded the 12V rail so that is wasn't doing 0 - 16A in .8 sec. Just having the unit idle at .2 A proved sufficient. We suspect that the switchmode supply couldn't kick in its regulation quick enough unless it had at least a small load and was regulating.
