PCIe 1x compatible w/ PCIe 4x?

[VirusType2]

I thought I heard someone say that a PCIe 1x card will work in a 4x slot. Is it backwards compatible?

I'm trying to let my brother use my eSATA controller, but he only has a PCIe 4x slot, and my controller is 1x.

Anyone know if this is compatible? (I don't even know if the slots are the same size, to be honest)


EDIT: I think I found the answer, thanks (forgot to look first before asking)

http://www.overclock.net/intel-motherboards/472418-can-pci-e-1x-go-into.html

 

[Vegeta897]

Yes. PCI-E 1x is compatible with PCI-E x4, x8, x16.

1x will fit in 4x slot.

 

[VirusType2]

Thanks, Veggie. Great news.

 

[Asus]

I can't remember which brand but someone was thinking of making a board with all X16 PCI Express slots. Could do multiple video cards or tv tuner or whatever 1x-16x card. That would be future proof assuming it had enough lanes or bandwidth behind it to use at the same time (chipset).