Hi spud2. Strange noises from inside a pc usually emanate from the processor cooling fan and ScanDisk at startup is usually caused by a bad shutdown which is not uncommon with Windows 98 and 98se. However they can also be caused by a failing hard drive. The best way to check is to remove the cover from your pc and use a piece of paper rolled up into a tube about 1cm diameter as a stethoscope to see if you can track down the source of the noise. I like to use paper for this because it is quite a good insulator and if it contacts a moving opject such as a fan blade it deflects rather than causing damage.