Enabling PCIe 2.0

[AphexDreamer]

This might sound like a very noobish question, but do I have to manually enable PCIe 2.0 or does is it automaticly used?

 

[Cold Storm]

This might sound like a very noobish question, but do I have to manually enable PCIe 2.0 or does is it automaticly used?

If the board supports 2.0 it should automatically be set on. I haven't seen any bios tool in any of my three boards that support it... It's just a auto. thing like x16 was. If the card has it, then you have it.

 

[DrPepper]

Yes it does it automatically as long as the card is PCIe 2.0

Cold Storm you post too fast

 

[panchoman]

you dont have to enable it, its just there.. pci 2 just allows more bandwidth and power over the pci bus, and if you have a pci 2.0 board, then its capable of the additional bandwidth and power over the pci bus, so if the card requires it, it'll use the additional resources, otherwise it wont

 

[AphexDreamer]

Ok, thanks guys.

 

[tdogg]

confirming PCIe 2.0 speed negotiation

PCIe 2.0 devices support both PCIe 1.1 and PCIe 2.0.
During initialization the devices link train at Gen 1 speeds . If the root complex supports it then the RC will attempt a speed change. If the Graphics card supports it and there are no issues then it will accept the speed change and the link will run an gEN 2 speed.
If the RC does not support it of if there is a problem running at Gen 2 it will drop down to gen 1.
To really know if you are running at Gen 2 speed you need to look at the PCIe link status register for that port on the Root Complex to determine what speed the link is presently running at.
APsoft has a 15 day trial utility to look at PCIe registers and you could use that tool to verify it is running at that rate. It has a human readable register decode but you have to know where to look. You could use PCItree (a shareware utility) to look at the registers as well but you need to know the port you are looking at and decode it which is complicated.

I would imagine some of these video vendors may be able to give you a status in their utility toolbox.
Some root complexes and video cards will automatically jump to 2.0 speeds during initial link training but that is not to spec.

Hope I havent confused you.
BTW the PCI-SIG hasnt even started official 2.0 testing in the compliance workshops . That will happen in september. I think it is fair to say there will be some wierd interactions on occasion until cards and chipsets start to get full 2.0 compliance.

Hope I havent geeked you out.
-Tdogg

 

[W1zzard]

GPU-Z will tell you your actual PCI-E speed.

for example

PCIE x16 2.0 @ x16 2.0 = runs in 2.0 mode
PCIE x16 @ x16 2.0 = mobo supports and advertises 2.0, but card does not run in 2.0 mode

 

[tdogg]

Nice man. Saves a headache
Thanks for the reply.

 

[AphexDreamer]

GPU-Z will tell you your actual PCI-E speed.

for example

PCIE x16 2.0 @ x16 2.0 = runs in 2.0 mode
PCIE x16 @ x16 2.0 = mobo supports and advertises 2.0, but card does not run in 2.0 mode

Yeah I have a 2.0 Card and a 2.0 Motherboard but niether is shown to be using 2.0. It just says PCI x16 @ x16? So now I'm thinking I might have to enable it, which I don't know exactly how?

 

[Nyte]

Yeah I have a 2.0 Card and a 2.0 Motherboard but niether is shown to be using 2.0. It just says PCI x16 @ x16? So now I'm thinking I might have to enable it, which I don't know exactly how?

What is your graphics card if I may ask?

 

[Hayder_Master]

i see you want to jump to 5ghz bandwidth it is good , you can see this thread of wile E run gpuz of card run as pci-e 2.0

http://forums.techpowerup.com/showthread.php?t=60445

 

[candle_86]

3870x2 isnt a 2.0 card thats your problem right there, the way they did crossfire with that bridge does not support PCIe 2.0