The worst thing about working with proprietary PC PSUs and motherboards is not knowing whether the AT/ATX connector is using a standard pinout. Sure, you can look at it and see if all the grounds are in the right place, and see if the main rails (+3.3, +5, +12) appear to be correct. Those aren't too hard, even if they use non-standard color codes, because it's easy to check ground continuity, and at least you can see if all the pins populated by main rails are the _same_ color, even if they're not the _right_ color, and then track that back to the PSU PCB and check voltage rating on output caps, etc. The thing that always makes me nervous is "all the other stuff." Did they drop -5v and replace it with +2.5v? Is PS_ON or P_OK inverted? Have they repurposed a ground pin for a remote sense pin on the +3.3v rail? You never know for 100% certain. _Usually_ it's all standard, because they're buying parts from OEMs that CAN customize a circuit, but why? What's the point of changing it unless you really need to? Anyway, that seed of doubt always makes me squint and chant, "please don't blow up please don't blow up please don't" while powering it on the first time.
E-MACHINES PCS ARE AWESOME!!
The worst thing about working with proprietary PC PSUs and motherboards is not knowing whether the AT/ATX connector is using a standard pinout.
Sure, you can look at it and see if all the grounds are in the right place, and see if the main rails (+3.3, +5, +12) appear to be correct. Those aren't too hard, even if they use non-standard color codes, because it's easy to check ground continuity, and at least you can see if all the pins populated by main rails are the _same_ color, even if they're not the _right_ color, and then track that back to the PSU PCB and check voltage rating on output caps, etc.
The thing that always makes me nervous is "all the other stuff." Did they drop -5v and replace it with +2.5v? Is PS_ON or P_OK inverted? Have they repurposed a ground pin for a remote sense pin on the +3.3v rail?
You never know for 100% certain. _Usually_ it's all standard, because they're buying parts from OEMs that CAN customize a circuit, but why? What's the point of changing it unless you really need to?
Anyway, that seed of doubt always makes me squint and chant, "please don't blow up please don't blow up please don't" while powering it on the first time.
Nice work on this one!
Well this doesn't happen often but first.
can i send you a 1000/1 jl amp for repair?
E-MACHINES PCS ARE GARBAGE!!