Can an old PCI 1.x motherboard use a PCI 2.0 video card?

I have an old machine that has an Asus A8N-SLI Deluxe motherboard (AMD 939 socket). The video card recently died, and as I was searching some of the online stores for a replacement, I ran across several comments in the feedback on several cards about being able to install PCI 2.0 video cards into a PCI 1.x slot, where they stated that the 2.0 video card would function fine, albeit at a 1% to 3% slower speed than if the card were actually in a PCI 2.0 slot.

Is this true?

If it is true, other than power supply considerations, are there any other tidbits I should be aware of if I were to do this?