Two little suggerstions:
- Swap the PSU for a brand new one (they come to be faulty);
- If you have enough skills, change the caps in the Toaster board. Change ALL electrolitics caps, they become faulty after some little time (~10 years):-D....
Do you use a Flyer? Check if the SCSI disks are working properly (format all disks, they are used for temporally store, anyway).