PCIe X1 IN PCIe X16 Slot.

Quick Question about PCIe X16 slots on the ASUS Sabertooth 990FX R2.0.

First the links, The board & a picture.

So I got the board, noticed I'd made a fatal error in judgement "assuming" it'd have 2 PCIe X1 slots like old board... but no, it has 1 (which is blocked by any 2 slots GPU in the top "tan" PCIe X16 slot. To fix this I tried moving the GPU to another slot, decided it was probably going to run slower & did some Googling. To my delight I discovered you can put PCIe X1,X4 & X8 in X16 slots (anything less than X16), it just doesn't use the rest of the lane.

I haven't had any time to do a side by side comparison X16 GPU only vs X16 & 2 X1's in X16 slots for performance. This is mainly down to Steam & Origin being... difficult with me for various nonsensical reasons.

GPU-Z is reporting that my GPU is running at X16 1.1 for some reason, could this be down to the other X1 cards? I've attached a screenie of what I mean.

:major2-BIT-GEEK:major

 

Sorry, but I am not following what you are trying to do. I note that board has,

3 x PCIe 2.0 x16 (dual x16 or x16/x8/x8) *1
1 x PCIe 2.0 x16 (x4 mode, black)
1 x PCIe 2.0 x1

*1: When running dual graphics cards, be sure to insert the card in the first and third PCIex16 slot to get the best performance.​

That tells me if you insert your graphics card in the first slot, you should still have at least the 3rd x16 slot. Yes, the x1 slot is covered, but you can put a x1 card in any of the other PCIe slots.

How many, and what type PCIe cards are you trying to install?

 

A pic would make this easier I think



It's a bit big, but as you can see my AMD 7870 is in PCIe 2.0 X16 slot 1 (Beige), my Creative Sound Blaster Z is in X16 2.0 slot 3 (Beige) & my wireless network card is in X16 2.0 slot 4 (Brown).

As I mentioned above the PCIe 2.0 X1 is covered by the dual slot GPU hence the query, the GPU is capable of running at X16 3.0, but is in an X16 2.0 slot & reports (from GPU-Z) say it's running at X16 1.1.

Hope this explains the situation & thanks for picking this topic up

:major2-BIT-GEEK:major

 

Then the only problem I see is the card appears to be running at X16 V1.1 instead of V2.0. I don't know why that would happen but I would check ASUS for current drivers (and BIOS) for your motherboard.

 

I updated the BIOS (UEFI) & now when I look at GPU-Z it still says v1.1, but but if I run the "PCI-Express Render Test" it changes to v2.0. Curiouser & curiouser! Could it be that it switches in games (load) & back down to save power when idle?

I've attached the GPU-Z report just after the test.

:major2-BIT-GEEK:major

 

Hmm, that does seem odd. And just to see what my system would do, I ran GPU-Z and I was surprised to see my PCIe V3 card running at V1.1, then suddenly it switched to 3 when I hovered over that reading.

 

Unless you are running an ASUS mobo & have some PCIe X1 cards in X16 slots, it must be a power saving thing when they are idle, or a false positive.

Case closed I guess, thanks for contributing though

:major2-BIT-GEEK:major

 

I wondering about the same thing. I note many of the newer motherboards support many "green" features. I also noted on the GPU-Z forum users reporting similar "issues" with other cards.

That said those "issues" do not appear to affect performance - so probably not anything to worry about.

 

I am all for "green" settings when they save you money & reduce the noise from the fans ect, but it's damned annoying when it gives false info.

It makes no sense that it should run at 1.1 anyway, that's data speed not power consumpton :confused

Shame it wasn't running slow really , I was hoping I could squeeze another year out of my 7870 what with Mantle arriving soon. I guess I can sell my old mobo, cpu & Ram as a barebones, my old 6870 (faulty BIOS) & this 7870, then that'll pay for a R9 280X

:major2-BIT-GEEK:major

 

Are you noticing any performance issues?

And remember, if you sell your motherboard and buy a new one, you will likely need to buy a new Windows license too as OEM/System Builders licenses stay with the "original equipment".

 

It's gone up, but then again I just replaced the CPU, mobo & RAM & should Indeed expect an increase in performance as I've upgraded from an AM2+ quad core to an AM3+ 8 core, DDR2 1066MHz RAM to DDR3 1600MHz RAM & I had the Samsung SSD before but it was running on SATA2 which was less than half speed. Well when I say it's increased I mean slightly (disappointingly). It's much more stable, BF4 used to be around 60=70 FPS, but dip down to about 30fps during heavy load (multiple explosions etc) & now it runs around 80-90fps never dropping below 60FPS (which is extremely playable). I have a feeling even with Mantle I'll still need a new GPU as it's most likely the bottleneck when it comes to games. 1920x1200 should run faster I feel

I hate it when you think you're done & a bottleneck appears :confused

I meant selling off my old stuff since I just upgraded :-D

:major2-BIT-GEEK:major