Pci-express speed

[pipes80]

Who can help with my problem?
My two GTX 580 on my x58a-oc, want work at full speed 16x but work only 8x.
Who know why?
Thanks in advanced

[Echoa]

Re: Pci-express speed

Who can help with my problem?
My two GTX 580 on my x58a-oc, want work at full speed 16x but work only 8x.
Who know why?
Thanks in advanced

its not an issue since you wont saturate the bus anyway

EDIT: didnt see the board, you might have them in the wrong PCIE slots? but even still doesnt matter as i said you wont saturate the bus anyway, also anymore info you can provide would be nice.

I.E
what have you tried already?, etc.


For both X16 you have to be in the slots labeled PCIEX16_1 and PCIEX16_2 which may not be right next to each other, look at the mobo and they will be labeled

[pipes80]

Re: Pci-express speed

its not an issue since you wont saturate the bus anyway

EDIT: didnt see the board, you might have them in the wrong PCIE slots? but even still doesnt matter as i said you wont saturate the bus anyway, also anymore info you can provide would be nice.

I.E
what have you tried already?, etc.


For both X16 you have to be in the slots labeled PCIEX16_1 and PCIEX16_2 which may not be right next to each other, look at the mobo and they will be labeled

x58a-oc is intel X58 and its lga 1366, I use two first pci express...I think for pci line stolen from to marvell sata usb3.0 controller and realteck lan

[profJim]

Re: Pci-express speed

From GIGABYTE - Motherboard - Socket 1366 - GA-X58A-OC (rev. 1.0) Specifications

1. 2 x PCI Express x16 slots, running at x16 (PCIEX16_1, PCIEX16_2)
   * For optimum performance, if only one PCI Express graphics card is to be installed, be sure to install it in the PCIEX16_1 slot; if you are installing two PCI Express graphics cards, it is recommended that you install them in the PCIEX16_1 and PCIEX16_2 slots.
   
   
2. 2 x PCI Express x16 slot, running at x8 (PCIEX8_1, PCIEX8_2)
   * The PCIEX8_1 slot shares bandwidth with the PCIEX16_1 slot and the PCIEX8_2 slot with PCIEX16_2. The PCIEX16_1/PCIEX16_2 slot will operate at up to x8 mode when the PCIEX8_1/PCIEX8_2 is populated.
   (The PCIEX16_1, PCIEX16_2, PCIEX8_1, and PCIEX8_2 slots conform to PCI Express 2.0 standard.)
   
   
3. 1 x PCI slot

This information should also be in your motherboard user manual.

[pipes80]

Re: Pci-express speed

From GIGABYTE - Motherboard - Socket 1366 - GA-X58A-OC (rev. 1.0) Specifications


This information should also be in your motherboard user manual.

Unfortunately I know the spec of the motherboard.
I was interested in finding a solution to the problem of reduced speed on slots 1 and 2

[Echoa]

Re: Pci-express speed

Unfortunately I know the spec of the motherboard.
I was interested in finding a solution to the problem of reduced speed on slots 1 and 2

do yo have anything populating the other PCIE slots? these are all guesses here from what you have given.

So from the provided info we can only assume you have something populating the other slots which means that it will automatically drop to x8. This as I said is not an issue though because you wont see a performance increase because you cant saturate the PCIE bus anyway and having x16 would be purely for aesthetic purposes anyway.

[pipes80]

Re: Pci-express speed

do yo have anything populating the other PCIE slots? these are all guesses here from what you have given.

So from the provided info we can only assume you have something populating the other slots which means that it will automatically drop to x8. This as I said is not an issue though because you wont see a performance increase because you cant saturate the PCIE bus anyway and having x16 would be purely for aesthetic purposes anyway.

No, only first two slot, maybe share pci express line with other controller?

[Echoa]

Re: Pci-express speed

No, only first two slot, maybe share pci express line with other controller?

Nope, either something's populating the other slots (doesn't have to be GPU), its been manually set to x8 in bios, or its bugged but I couldn't tell you and I don't know what you have done to try and fix it. Like I said, it's not really an issue as you can't saturate the bus anyway so unless you're having issues I'd not worry about it

[pipes80]

Re: Pci-express speed

Nope, either something's populating the other slots (doesn't have to be GPU), its been manually set to x8 in bios, or its bugged but I couldn't tell you and I don't know what you have done to try and fix it. Like I said, it's not really an issue as you can't saturate the bus anyway so unless you're having issues I'd not worry about it

I think for controller pcix (marvell 9182 sata 6g and realetek lan and usb 3.0 controllers)

[Vinster]

Re: Pci-express speed

they wouldn't publish those ports as being 16x and not provide it due to on-board gear.

how do you know they are running at 8x?

Vin

EDIT: here is a bench from HWBot where a guy did it with the same gear... So it's possible... alancsalt`s Aquamark score: 332928 marks with a GeForce GTX 580

[parsec]

Re: Pci-express speed

x58a-oc is intel X58 and its lga 1366, I use two first pci express...I think for pci line stolen from to marvell sata usb3.0 controller and realteck lan

It seems like he is using the PCIEX16_1 slot, and the PCIEX8_1 slot, going by "two first pci express".

The order of the four PCIe x16 slots on this board are, from top to bottom:

1. PCIEX16_1

2. PCIEX8_1

3. PCIEX16_2

4. PCIEX8_2

Two video cards must be in slots 1 and 3 for both of them to run at x16.

If two video cards are in slots 1 and 2, both will run at x8, from the specs:

The PCIEX16_1 slot will operate at up to x8 mode when the PCIEX8_1 is populated.

"I use two first pci express", or slots 1 and 2, which would explain the x8 speed on both cards perfectly.

The x16 slots on this board are labeled the same as I have listed them above.