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PCI-express running at 2.0 x2 not x16

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Joined
5 Apr 2008
Posts
1,526
Hey guys,

Both in the BIOS, and the AMD driver it says it is running at PCI-express 2.0 x2 mode.

My motherboard Asus H81l-PLUS has only 1 PCI-e slot and that is 2.0 x16.

Im using a Sapphire R9 380 with a Corsair RM550 power supply. I made my own case in which the graphics card is parallel to the motherboard, hence i am using a riser cable (but cant see why this would be the cause).

Things tried:
Re-seated gpu (with riser cable).
Flashed Motherboard
Reset motherboard to defaults.
Set motherboard pci-e speed to '2.0'
Set motherboard bios to high performance mode
Set windows to high performance mode

Things not tried:
Put gpu directly in motherboard without riser (would mean completely dismantling PC to fit it in).
Using a 'powered' riser (with a molex connector). From what i have read this shouldnt be necessary and is usually used to give PCI-e x1 slots extra power to upgrade it to x16.


EDIT:
Worth taking the CMOS battery out?
 
Last edited:
If you are using a riser then I would check that it is a full x16 riser and not just slotted as x16.

Description for the riser i bought is as follows:



Install PCI-E device freely according to dimension and position of computer case.

Ideal for small computer & server case, like 1U & 2U.

One end is PCI-E 16X male and another end is PCI-E 16X female.

Gold plated contacts for best connectivity and long life.

No Driver necessary and jump-less.

The Flexible Single Slot PCI-Express 16x Riser Card makes the PCI-Express 16x Card away from motherboard,with the PCI-Express socket directly in line with the socket on the motherboard..

PCI Express Specification Version 1.0 Compliant.

Fits 1U / 2U Rackmount Chassis.

Total Legth 23cm ( 9in )

It says 'Version 1.0 compliant' ... Is this a problem considering I'm aiming for Version 2.0 x16? I thought it was just a cable?!

Here is a picture

_10_zpszl1iu8k6.jpg
 
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You're just going to have to bite the bullet and dismantle it to test. There's no other way to rule out the riser as the cause.

worked just fine with the gpu directly in the motherboard. made me conclude that the riser was at fault. anyway, i then tried the riser one last time and it worked weirdly! Now its running no problem at x16 speed
 
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