Check the capacitors on the motherboard for signs of swelling and/or leakage. http://www.badcaps.net/
If it's an older board the power supply upgrade may not have helped as the older boards used the 5V rail extensively, unlike later boards which use the +12V mostly. Newer power supplies tend to be weighted to the +12V rail(s).
The Rebels Haven has lots of info on ECS socket A boards. http://www.rebelshavenforum.co...n/ul...i?ubb=forum;f=1
MSI K7N2 Delta2 LSR|35w XP-M2400 11x214 1.62V|2x512MB OCZ EL 2 2 2 11 2.9V|9600XT|Seasonic 350w
Abit AN7|XP-M2800 10.5x227 1.62V|2x512MB Mushkin XP4000 2 3 2 11 3.2V|9600XT|Seasonic 550w
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