It needing caps must be a high priority, but to test it, remove all the RAM from the Q605 and see if it boots with less RAM. Then take the RAM out of the LC475 and put it in the Q605 and test that. Final tests is to remove the hard drive and see if you get a floppy disk with a flashing "?" and replace it with the one from the LC475.
Sometimes the Chimes of Death are from a bad boot blocks on the hard drive. Depending on the machine and where it fails, most of the time it brings up a Sad Mac but there are times when it wont and only give you the Chimes.
If you worry about doing a recap yourself, Uniserver does a great job for reasonable price.