Running PCI-e 3.0 slot in 2.0 mode?

[lordrocky]

Ok, so I'm not really sure if this is even possible, but I had a thought.

I'm in the process of building a machine, and I was wondering if I bought a motherboard with 3 PCI-e 3.0 slots, (With my Intel 4770K only having 16 PCI-1 3.0 lanes available), is it possible to change one of the slots to 2.0 so that it doesn't use any of the 3.0 lanes?

I have other cards such as a thunderbolt card and a SSD that use PCI-e 2.0 and would rather them not be taking the bandwidth from my video cards if I can help it.

The only motherboard I've found that has the right amount of 2.0 slots is also $200 out of my price range, so any assistance with this would be appreciated.

Again, I'm not even sure if they're switchable to a lower mode.

 

[IDontUnderstand]

What motherboard are you speaking of?
Usually you can just plug those cards into non x16 lanes.

 

[Someone Somewhere]

Generally not a good idea (and I'm fairly sure it's not possible) - the chipset is the only provider of PCIe2.0, and that's only 8 lanes, including any add-in chips, like SATA or extra USB3.0 ports.

 

[lordrocky]

The motherboards I'm looking at are the Asus Maximus VI series.
I would be more than happy to plus them into non x16 lanes, but the two cards I'm looking to add are x2 and x4, but there's only one x4 slot on the Gene, and only x1 slots on the Formula. The Extreme has all the slots I need, but it's out of my price range.
If I can get the Formula, and use the other lanes as 2.0 that could solve my problems, at least until I decide to upgrade to an SLI config.

 

[Someone Somewhere]

Hmm. Until you SLI/CF, any board with x8/x8 SLI/CF should be fine, because they usually have an x4-wired third slot. PCIe3.0x8 is enough for any current GPU.

I don't think there are any boards that can do what you want, though, as you'd need 2x4 lane slots off the PCH. Which isn't going to happen.

You may need to consider picking up an mSATA SSD instead, or getting a board with Thunderbolt built in, e.g. the GA-Z87X-UD5 TH.

 

[lordrocky]

Good to know. I've been looking at both that one and the Asus Z87 Deluxe/Quad as well. I guess I'll just have to figure how much extra I'm willing to shell out. The battle between saving on costs and future proofing rages on...

 

[Someone Somewhere]

That board is cheaper than most of the ROG stuff.

Unless you've got a particular reason to use TB, I'd drop it and get a ~$130 board. I doubt it's going to take off much; IMHO it's the new Firewire.