power supply question

[AAACHIPSET]

my a1200 has had a problem with the usb ever since i got it ..i  have always thought it was a power supply problem ..now im convinced ..the machine runs for hours if usb is not enabled..ie: hardware disconnected ..if i plug in i get an hour tops before the usb drops the mouse an anything else i plug in to usb ie: 4 gig usb flash card  makes the crash even sooner ..wont talk about 16gig card ..lucky if that even survives loading  ..i have a 030 accel  card indivision aga card ..4 gig sdcard as main drive ..an 2.5 to 3.5 adaptor to the dvd drive..i use a a500 brick  but its not enough power now i think ..
im not  a electrician so not confident in adapting a power supply ..an dont want to blow my 1200  to bits ..suggestions  please ?

[AAACHIPSET]

using  a a500 original  power supply ..run the usb after 10 mins  crash ..lid off  to see if getting to hot  same  thing .. cant believe usb would pull that much power  ..anything in the configs i should check  ..maybe a driver  is crashing out ? ..unplugged my external floppy  ..doesnt crash if it on  an usb is not..all a bit weird..power or not power ..thats the question ..

[AAACHIPSET]

my a1200 has had a problem with the usb ever since i got it ..i  have always thought it was a power supply problem ..now im convinced ..the machine runs for hours if usb is not enabled..ie: hardware disconnected ..if i plug in i get an hour tops before the usb drops the mouse an anything else i plug in to usb ie: 4 gig usb flash card  makes the crash even sooner ..wont talk about 16gig card ..lucky if that even survives loading  ..i have a 030 accel  card indivision aga card ..4 gig sdcard as main drive ..an 2.5 to 3.5 adaptor to the dvd drive..i use a a500 brick  but its not enough power now i think ..
im not  a electrician so not confident in adapting a power supply ..an dont want to blow my 1200  to bits ..suggestions  please ?

just a follow up for those interested ..i did a complete check on all cables attached to everything ..the usb connection was a tad loose so i pushed it in hard an on the clock port as well ..also the connector to the indivision had the usb connector sitting on it so i put some tape around the ends of the usb just in case heat from the board was causing problems  ..moved my ide 2 to 3 inch further to the left away from everything basically giving everything breathing room ..did a reinstall an didnt enable the usb to boot at startup ..guess what problem going away ..except when i plug a usb mouse in ..after 10 20 mins the driver for the mouse just falls off an total freeze ..usb flash cards can run doom for hours  no problems ..even when both the 16gig an 2 gig are both plugged in ...all that checking  etc ..an i think it was the mouse all along..go figure ..