PCI-E X16 lane only running at X4 on GA-P55-UD5

Cesar67

Cesar67

Cesar67

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Posted in the graphics section but, I think it may be an issue other than the card itself.

EDIT:

Seems this guy had a very similar issue, Reseting the CMOS apparently did the trick for him however, I have tried this and still X4 !

I just noticed last night my card was running at X4 instead of X16 when i looked at CPU-Z:

24l24ae.jpg


I'll list my specs just now

GA-P55-UD5
Intel I5 750
Sapphire 5850
Intel X25-M 80GB
WD Caviar Green 1.5TB SATA-II
Corsair HX650

Maybe this has happened when i installed Windows 7 ?

Definitely installed in the X16 slot. No other expansion cards installed.

In the BIOS, Init display was PCI when the operating system was installed (Should have been PEG).

Changing to PEG doesn't alter what i see reported in CPU-Z - Still X4

I know this board shares bandwidth, I only have the one graphics card installed. I uninstalled it, Cleaned the contacts and reinstalled with no joy.

From what i can tell, This MOBO has SATA running off the P55 chip and GSATA which i guess is the Gigabyte SATA chip.

My SSD and HDD and DVD-RW run on the P55 SATA chip, Nothing at all on the GSATA (Won't boot if i disable this) controller.

I don't have any e-SATA ports in use either.

Anyone got any idea what is going on ? Any advice ?
 
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Strange. Exactly the same mobo as me and mine reports x16 in the top slot no probs. I've never fiddles with any BIOS options to achieve that.

Have you tried a clear CMOS or just load optimised defaults? Write down your overclock settings beforehand of course. I also notice you're on an older BIOS. I'm on F9d and had various problems on older versions (though never noticed this one). Might be worth a try. I believe there's a newer still F10 version out also. I'll have a look in BIOS and see if there are any obvious settings that might be the cause, but as I say I've never touched anything other than overclock settings.
 
Tried it in the X8 slot, wouldn't output any display.

Yeah, I wil update the BIOS.

Going to try fresh clean default settings when I get home.
 
Updated to BIOS F10. Still X4 !

Would re-installing windows set the PCI-E X16 lane back to X16 ?

Is this set on POST or when the OS is configured ?
 
your definitely got it in the top slot? only ask because the very bottom 16Xpci-e slot runs at 4X speed on these boards.
 
Is your CPU overclocked? the PCI-E lanes are built into LGA1156 processors so maybe overclocking is causing some unusual side effects?

There is no such think as a P55 chip or northbridge, only a CPU and ICH10 (Southbridge) in P55 motherboards.
 
Cesar67 said:
Updated to BIOS F10. Still X4 !

Would re-installing windows set the PCI-E X16 lane back to X16 ?

Is this set on POST or when the OS is configured ?
Click to expand...

Hmmm - would have thought it was set in BIOS, but have you installed the chipset drivers in windows? And you deffo tried a load optimised defaults after you flashed the new bios? Everything running at stock?

CPUZ bug (you have a later version than me)? Long shot there I think. You're definately sure you are running at 4x with crippled performance?

Hmmmmmmmmmmmmm
 
stulid said:
your definitely got it in the top slot? only ask because the very bottom 16Xpci-e slot runs at 4X speed on these boards.
Click to expand...

I have a Zalman VF3000-A fitted so it's three slots wide, Would only fit in the X16 or the X8.

Tried it in the X8 and it wouldn't output any display.

mmj_uk said:
Is your CPU overclocked? the PCI-E lanes are built into LGA1156 processors so maybe overclocking is causing some unusual side effects?

There is no such think as a P55 chip or northbridge, only a CPU and ICH10 (Southbridge) in P55 motherboards.
Click to expand...

All at stock after updating the BIOS.

I was just thinking the SATA is sharing bandwidth, I read about the e-SATA being in use would disable some other features.

Liampope said:
Hmmm - would have thought it was set in BIOS, but have you installed the chipset drivers in windows? And you deffo tried a load optimised defaults after you flashed the new bios? Everything running at stock?

CPUZ bug (you have a later version than me)? Long shot there I think. You're definately sure you are running at 4x with crippled performance?

Hmmmmmmmmmmmmm
Click to expand...

Yep, Tried optimized, Tried a few small tweaks to see if i could change it too. No dice !

2livcxk.jpg

2ni5d81.jpg


Three apps all say X4 !

To be honest, In BFBC2 i still get over 100 FPS so, I don't really know how 'crippled' my card is running on X4.

The hardware 'should' run at X16 so, I want it running at X16.

I was thinking of adding another 5850 if i could get one with decent cooling.

There won't be any jumper for this ? On the card or the MOBO ?
 
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No jumper for me. What I dont have is that x.x on the mainboard section of CPU-Z - not sure what that is. As far as I'm aware, nothing should share bandwidth with the x16 slot. Hmmmmmmmmm. Email to Gigabyte?
 
Yep, Just sent a ticket to Gigabyte, Not expecting much help to be honest. We'll see.

I think* the x.x should be where the motherboard version number should go ?

There is only one version of this board as far as i am aware.

Cheers Ryan.

I only updated my BIOS to see if it fixed this issue for me mate, I was running F8 no problems at all, Even had it @4.2GHz for a while.

If it's not broke ...
 
I thought I would add it just to see if you can make any comparisons. Guess not :(

Have you tried the card in another PC to see if its the PCI-E slot or the card?
 
Ryan111 said:
I thought I would add it just to see if you can make any comparisons. Guess not :(

Have you tried the card in another PC to see if its the PCI-E slot or the card?
Click to expand...

I have an old system i can fling together to test it with aye, I have better things to do though :)

HazardO said:
It's nothing to do with the OS. Much more likely a faulty CPU, GPU.
Click to expand...

I just put that out there for some opinions, I guessed it would be set at POST.

So, You think possibly the CPU could be faulty ?

I was thinking maybe the motherboard.

Hopefully it's not the card as i have put a third party cooler on it so, That will be my warranty void.

Still waiting to hear from Gigabyte.

EDIT: Edited the first post with someone over at overclock.net with a very similar issue.

According to this PCI-E scaling comparison I'm only losing 5% performance anyway :D
 
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make sure the gfx card is in the primary slot and that it is set correctly.
If your motherboard has USB 3.0 and Sata 6 make sure that IO levelup is turned off (This is what it is called on Asus boards as it reduces gfx bandwidth to increase Sata and USB bandwidth and thus speeds).
 
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