Anyone familiar with the Asus P5Q Pro?

[Magnetar]

I would like to install a USB 3.0 PCI-e card.

I've had my Asus P5Q Pro for sometime now and I can't remember something particular about my PCI-e x16 slots.
I'm hoping someone else here has this board and remembers their research.

When I use one video card, the blue PCI-e x16 is running a full x16; that parts fine.
When I use the other (crossfire port) PCI-e x16 it's actually runs at x8. If there were to video cards, both would run at x8.

Seeing as how I'm already using my two available PCI-e x1 ports, I would like to know if I can use the second PCI-e x16 port at whatever speed, without it turning down the blue PCI-e x16 where my video card is to X8.
Is there anyway?

As far as I remember (which isn't too well) even if Crossfire is turned of, it will still down grade the port due to the how many channels the chipset has.

Please help?

[_dangtx_]

the only way to find out is to try it :)

dont think you'll see any funny stuff in your games,report back if you do though

[MARSTG]

I think the issue is that even if you put something else in that port, even without being a video card, the BIOS will split the available 16x lanes into 2 dual 8x. Like for example I have a SLI board and used a PCIE 4x card LSI SAS controller in the second one, but given the fact that the ports are Gen2, even if it was in 8x mode, it was the equivalent of first generation at 16x. I did not notice any issues whatsover during gaming.

[Borg]

2 x PCI Express 2.0 x16 slots, support ATI CrossFireX™ technology at x8 link
(PCIe x16_1 blue, PCIe x16_2 black*)
3 x PCI Express x1 slots
2 x PCI slots
*PCI Express x16_2 slot (black at max. x8 link)

I suspect it will downgrade speed to dual x8.

[Magnetar]

Thanks for the feedback all I really appreciate it!

Yeah, I'm pretty sure it will downgrade it.
I checked the BIOS again, and there isn't anything anywhere to turn crossfire on or off. If I could ensure it was off I'd have a chance.

Does anyone recall if any programs like GPU-Z or something will tell me if the blue slot is running at x16 or x8?
Other wise the only way I can think of being able to tell is running benchmarks again with and without the USB3.0 PCI-e card installed.

I'm running a GTX 285, so I'm thinking that I'd see a difference in gaming (and benchmarks) if the Blue PCI-e slot were to downgrade to x8.

Thank again all!!

[tabasko]

Yes, GPUz will tell you that, it's the bus interface. I have the p5q pro but unfortunately i don't have another card to plug in, else i would've been able to help you =(

As far as I know though, changing from 16x to 8x will be 2-3fps so I wouldn't worry too much.

[Dr_BenD_over]

GPU-Z or CPU-Z will tell you what speed. I wouldn't think the impact would be all that great given the PCI-E 2.0 slot and the single core 285.

[Magnetar]

Thanks for the feedback!

So, I'm feeling fairly confident that using my other PCIex16 (x8) slot, (thus changing my Blue PCIe x16 where my video card is from 16x to 8x) will only reduce my FPS by several frames! Bot that bad at all.

That said, the question does arise, down the road when I get a new card (GTX585, GTX685 or whatever...) how much will that cripple me?
I understand, this question may be difficult to answer accurately (or it might be easy to answer lol), but anyone's best guess is also welcome.

Thanks again all!!

[Deviant]

^
Minimal if anything. If I recall, it was less than 3% between 8x and 16x in recent reviews where the conclusion said the changes were overall, negligible and wouldn't make it or break it for you.

[enaberif]

Originally Posted by Magnetar

Thanks for the feedback!

So, I'm feeling fairly confident that using my other PCIex16 (x8) slot, (thus changing my Blue PCIe x16 where my video card is from 16x to 8x) will only reduce my FPS by several frames! Bot that bad at all.

That said, the question does arise, down the road when I get a new card (GTX585, GTX685 or whatever...) how much will that cripple me?
I understand, this question may be difficult to answer accurately (or it might be easy to answer lol), but anyone's best guess is also welcome.

Thanks again all!!

Difference between 8x and 16x is so minimal that even on a high end card you'll see almost NO difference.