I mean, whatever PC I had in 1999 was definitely already several years old and probably wasn't top of the line at the time of purchase. So it was probably closer to 200 MHz than 1GHz.
Pretty sure when Bleem came out I was still rocking the 166Mhz 64MB family computer running windows 95 or 98. If memory serves, I was able to play Crash Bandicoot at not-quite full speed.
I owned a laptop shortly after that which was somewhere in the 200mhz-400mhz range that played PS games at full speed.
Yeah, I actually owned Bleem even though I had a PlayStation. I think I still have the CD.
I still was impressed at the time for the PC version, not only for getting it to work on a PC but the amount of reverse engineering that he was able to do with zero information.
Bleemcast on a 200MHz CPU is more impressive.