questions about the ati HD5850 and 16x pci-e

I plan to upgrade my 8800 gta 512mb card soon and I got my eyes on that ati xfx HD5850 black edition, but I got a old 16x pci-e, will it work with it? if yes, will I see a big difference vs someone with a pcie-2.0 slot?

Thanks

will work fine, just a wee bit slower.

yes it'll work; but the 2.0 slots give double the bandwidth.smc91352