Controller card opinions, does this make sense?

[Rmcky]

My old motherboards only supported ATA33 and, since my HDDs supported UDMA 100, I added a Promise controller card to each, an Ultra 66 in one and an Ultra 100 in the other.

I liked this setup for several reasons, first, the drives did seem a bit faster, but additionally it allowed me to run both my burner and DVD drive as masters on the original IDE ports of the motherboard. These drives seemed more efficient that way, too.

My new motherboards have onboard ATA66 support and during setup, I used it for my HDD, then used the second ATA33 port for my CD devices, the burner as master and the DVD drive as slave.

I'm wondering if there would be any advantage or disadvatage to installing the Promise cards and switching my setup to the same as I had the old systems. Do you think the controller card running on an additional PCI bus would be actually be somewhat of a bottleneck or would it be just about as efficient as the onboard?

I know I can experiment with this and see how it works out, but determining drive efficiency is such a subjective matter. Just wondered if anyone had any knowledge or opinions about this.

Thanks, Rick

[NDD]

I guess using add-on card is better then using o/b IDE, even if they both ATA66, for example. I put my IBM 75GXP 45GB ATA100 on HPT370 instead of on o/b ATA100, and it seems to run faster, especially when copying between disks (which I do many times).
Add-on cotroller shoudn't be a "botttleneck", since it even frees CPU from processing data from o/b IDE channels.

Best Regards ...