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I was under the impression that PCIE cards werent even using all the bandwidth they currently had.

 

Smaller importance as compared to what? I'm not talking about performance, I'm talking about straight up building a new rig. Say I buy a new mother board and it is all PCIe 2.0. I don't think my "G80" would work would it? I buy R600, put it on my PCIe 1.0 mobo, then buy a new mobo(PCIe2.0), and swap in R600 with no issues.

Anyways, from what I can gather on RD790, it has 4 PCIe slots. 2 of them will be PCIe 1.0, and the other two will be PCIe 2.0. I soppose that is a great move on AMD's part considering a current PCIe 1.0 video card owner may want to upgrade to the mother board.

I'm aware of the bandwith not being all that important. What matters here though is the life in ones purchase.

 

Actually, yes it would work just fine.
PCIe 2.0 is retro and forward compatible, both in terms of the motherboard and of the add-in cards used.

And you can do exactly the same with any other PCI-Express card available now.

PCIe will only be of substantial use to Turbocache/Hypermemory schemes used in low end GPU's and/or IGP's, since they depend on main RAM access.
Even with a full 32 lane PCI-Express 2.0 path , a GPU with a mere 8GB/s upstream BW and 8GB/s downstream BW is still way crippled compared to the internal bandwidth of top end GPU's (as i previously mentioned).
A standard G80 GTX has ~80GB/s, while the R600 was previously in the ~150GB/s range, until the memory type and speed got downgraded, apparently.

 

Why do you think that? There is this thing called backward compatiblity: AGP x1 still working in AGP x2,x4,x8 slots. USB 1.1 devices still working with USB 2.0 hosts. PCI1.0 still working in early PCI2.0 slots.

etc. etc.etc.

The developers of PCIe2.0 would be insane not to allow this. And, surprise!, there is this tool called Google that allowed me to come up with this. It's a complicated world...

 

offtopic:
AGP x1 (and AGP x2?) 3.3V signaling cards don't work in AGP x8 slot.

 

Some do.
There is a version of the slot called "AGP Universal", used in a limited number of motherboard models.

 

I don't know any single AGP8x MB supporitng 3,3V signaling. There are only some graphics cards, which support 8x transfers + AGP1x/2x 3,3V signaling (e.g. RV280)...

 

this cleared it up for me as well.

http://en.wikipedia.org/wiki/PCI_Express#PCI_Express_2.0

 

AOpen AK79G Max (Nforce 2), with a simple googling.
Notice the keyless AGP Universal slot.

 

Last week Tom's Hardware published PCI-E scaling analysis. It shows that x16 is useful at times.
http://www.tomshardware.com/2007/03/27/pci_express_scaling_analysis/

 

Yes, but in actual games the difference between x8 and x16 is already pretty negligible, and the tendency to see any real world discrepancies will only diminish with further increased theoretical bandwidth.
Certainly there isn't going to be any sort of linear increase in performance due to PCIe 2.0.

 

It's quite curious how GF8800 is so much more bandwidth sensitive than X1950

 

Indeed.
That's another interesting aspect to compare with G80, once R600 is out.

 

Slot is universal, but not 3,3V compatible.... nF2 doesn't support 3,3V signaling. Read last 4 paragraphs:

http://www.pcstats.com/articleview.cfm?articleID=1365

 

Which will have what practical use exactly? Just don't tell me that anyone sane would run any of those boards with less than PCIe x16.

 

Here is a longer version of a german interview of Vijay sharma ( now in english )
http://www.pcgameshardware.de/?article_id=573129

 

Not on purpose....yeah yeah STFU

 

Actually, i was thinking PCIe 1.0a/1.1 vs PCIe 2.0.

 

It's April 1st already it seems
http://www.techarp.com/showarticle.aspx?artno=392&pgno=0