Beige G3 with PCI SATA card and maxing out at 10MB/sec transfer rates on SSD

[MacKilRoy]

I decided to put a PCI SATA card inside my beige G3 and connect a SATA SSD to it, for reliability, sound levels, and above all, speed.

However, I noticed I can only get about 10MB/sec throughput. Either by duplicating on the same disk, or copying between disks.

I read the PCI bus on the beige G3 is supposed to support max transfers of 266MB/sec and while I get that I won’t see the max rate, why is it so low?