Wow.. Congratulations, Machforr! I would be glad to add your method to the guide. Hopefully, affected users of the P5KPL-CM motherboard will be able to use it to fix the problem. +rep!
How To Fix The PCI Express x1 Bug Rev. 4.0 User of ASUS and Gigabyte motherboards (maybe others as well) may be affected by a PCI Express x1 bug which causes a tremendous drop in performance. ChampionLLY takes a look at the motherboards and graphics cards affected by this problem and what solutions work, and what doesn’t. In the second part, he takes a look at the effect that PCI Express x1 bug has on the performance of your system. The results will shock you. Here are the latest updates in Revision 4.0 : Link : How To Fix The PCI Express x1 Bug Rev. 4.0
How To Fix The PCI Express x1 Bug Rev. 4.1 User of ASUS and Gigabyte motherboards (maybe others as well) may be affected by a PCI Express x1 bug which causes a tremendous drop in performance. ChampionLLY takes a look at the motherboards and graphics cards affected by this problem and what solutions work, and what doesn’t. In the second part, he takes a look at the effect that PCI Express x1 bug has on the performance of your system. The results will shock you. Here are the latest updates in Revision 4.1 : Link : How To Fix The PCI Express x1 Bug Rev. 4.1
More to add... Hi! I don't have a tip on fixing his bug, but I recently encountered this and noticed that my mobo/gfx combo wasn't listed in the article. I'm running ASUS M4A88T-M/USB3 mobo, and Radeon HD 6850 gfx. I recently installed a wireless card in the PCIE x1 slot above the video card and apparently bumped it. Reseating the card fixed it, but I was seriously panicing there for a minute! Thanks for the article! Nice work!
Oh, you bumped the Radeon HD 6850 and it didn't BSOD the system? Well, I'm glad you fixed it! Will add your experience to the guide. Thanks!
I have P5B motherboard running quad core Q9300 on 3GHz, FSB 400(1600), Radeon 5790, 6GB DDR2 on 800MHz, HDD 500GB, DVD burner and lots of different fans. This motherboard is rated 1066 max. and its running 1600.I fixed the PCI-e x1 problem by raising voltage on NB by one step, from 1,2v to 1,45V. Problem with this MB is that AUTO regulation of North Bridge is not working correct.AUTO mode should raise voltage when NB needs it but it doesnt.It keeps it at 1,2V. At least not always.Sometimes it does, but most of the time it doesnt. It is easy to fix this by manualy raising voltage.NB on this speed simply need more power.If manualy raising voltage doesn help, then raise it more (on your own risk). It would be good to put some fan on NB heatsink. If raising voltage on NB doesnt help then Your motherboard just isnt capable to run on that speed. Conclusion is that you dont need miracle BIOS fix to solve this problem. Just set the NB voltage manualy.
How To Fix The PCI Express x1 Bug Rev. 4.2 User of ASUS and Gigabyte motherboards (maybe others as well) may be affected by a PCI Express x1 bug which causes a tremendous drop in performance. ChampionLLY takes a look at the motherboards and graphics cards affected by this problem and what solutions work, and what doesn’t. In the second part, he takes a look at the effect that PCI Express x1 bug has on the performance of your system. The results will shock you. Here are the latest updates in Revision 4.2 : Many thanks to rade486 and bg4m3r! Link : How To Fix The PCI Express x1 Bug Rev. 4.2
Update ! I need to update this! Yes, you have to set NB voltage option to manual so you could get x16 speed on ASUS P5B .But you have to find right voltage for your specific configuration.It doesn't have to be raised in all cases as I said before.After upgrading my PSU to much stronger one I had to set NB voltage to lowest setting and that is 1,25V.So, the solution is to set NB voltage option to manual and find the right voltage starting from lowest value and rising voltage till you find the right one.Please update article.
How To Fix The PCI Express x1 Bug Rev. 4.3 User of ASUS and Gigabyte motherboards (maybe others as well) may be affected by a PCI Express x1 bug which causes a tremendous drop in performance. ChampionLLY takes a look at the motherboards and graphics cards affected by this problem and what solutions work, and what doesn’t. In the second part, he takes a look at the effect that PCI Express x1 bug has on the performance of your system. The results will shock you. Here are the latest updates in Revision 4.3 : Many thanks to rade486! Link : How To Fix The PCI Express x1 Bug Rev. 4.3