New HD and PCI controller card

I recently purchased a Western Digital 20G HD, I have a Compaq Presario with a 3GHD. I bought it at Best Buy, and I asked the tech there if I could use the Siig ATA66 IDE Controller card with this hard drive they said yes. My current computer is ATA33. Every time I installed the card I got a BIOS error, but if I disconnected it and hooked it to the cable of my current drive, it worked. Finally, I got on the Siig website and found an update that said if you were having problems with the BIOS, and/or had a Western Digital download this BIOS. I did, it stopped the BIOS error, but my pc kept hanging up, so I reinstalled my current BIOS and everything seems to be working, except where I had one partition, my new drive is D:, the partition is F:, it will not access this. I contacted the Compaq support tech's, they said "sorry" as far as we know no one has been able to use a ATA66 controller card with a Presario". I am pretty satisfied with the way it is running for the most part, but how can I tell if it is running at ATA66? Or does someone know of a better setup to do this? I had to set both drives at "cable select" with the jumpers, via tech's advice. Any help would be appreciated....