Noctua NH-D14 not clearing first PCI-E x1 slot on mobo

[m3ta1head]

Installed my new D14 yesterday, needless to say it was a bit of a squeeze. I was having problems getting it to sit straight-the darn thing kept wanting to rotate slightly to the left. I remounted both the hsf and bracket several times in an attempt to get it straight. This is as good as I could get it:

The bottom of the D14 was actually touching the solder joints on the back of the STX and shorting it out! For now, I've resorted to spacing them apart with a credit card, but a more permanent solution is needed. I can move the STX to the slot immediately below my 7950, but that will block airflow to the card significantly. I can put it in the second pci-e x16 slot, but that will throttle both slots back to x8. I've also tried moving the 7950 to the bottom x16 slot, but the heatsink on the card does not clear the power/reset headers for the case. Whoever laid this board out should be shot!

Anyone have any suggestions on how to rearrange/fix things, short of going out and buying a new mobo?

 

[Vectronic]

[Image 1] Holy s**t dude that's close!
[Image 2] Oh ok, he put something in between.
[Comment] Yup...

Will it really throttle PCIE2 if you put the STX in PCIE4? I mean the STX can't be using x16 or even x8, PCIE4 should be able to run at x1 or x4 without throttling PCIE2.

I have more suggestions, but they require skills, or spare PC parts.

 

[m3ta1head]

Will it really throttle PCIE2 if you put the STX in PCIE4? I mean the STX can't be using x16 or even x8, PCIE4 should be able to run at x1 or x4 without throttling PCIE2.

I am actually unsure regarding this, could someone please clarify?

 

[Vectronic]

You should be able to verify it yourself by reading the manual, download it if you don't have it.

It claims to do x16 + x8, and it might... P67, has 8 PCI-E Lanes at 1, 2 or 4x, so:

x1 / 1 = 1
x16 / 4 = 4
x1 / 1 = 1
x1 / 1 = 1
x8 / 4 = 2

9... we're one over 8... but, if x8 is running at x1, or x4, that's only 1 lane, which makes 8 total... but one lane is being split off into the 2 PCI... so... 7... we can't get 7 without dropping a lane from the x16 unless the second chip can run both PCIs and a x1 PCI-E.

So lets look into this... since MSI doesn't provide much information about their boards, we look for an image (or at your board since you have one).

ASMedia ASM1083... supports 3 PCI masters, 2 of those are going to the PCI slots, the third is probably going to the VIA VT6308P.

So, we're screwed here... looks like you won't be able to run your x16 @ x16... x12 at best.

But, x8 would be fast enough anyways, you might drop a frame.

Granted, this is still partially speculation and it might actually be able to turn off one of the x1 slots, and still run the x16 @ 16, even with your x8 in use.

You could always, you know... plug it in and find out...lol

 

[m3ta1head]

You should be able to verify it yourself by reading the manual, download it if you don't have it.

It claims to do x16 + x8, and it might... P67, has 8 PCI-E Lanes at 1, 2 or 4x, so:

x1 / 1 = 1
x16 / 4 = 4
x1 / 1 = 1
x1 / 1 = 1
x8 / 4 = 2

9... we're one over 8... but, if x8 is running at x1, or x4, that's only 1 lane, which makes 8 total... but one lane is being split off into the 2 PCI... so... 7... we can't get 7 without dropping a lane from the x16 unless the second chip can run both PCIs and a x1 PCI-E.

So lets look into this... since MSI doesn't provide much information about their boards, we look for an image (or at your board since you have one).

ASMedia ASM1083... supports 3 PCI masters, 2 of those are going to the PCI slots, the third is probably going to the VIA VT6308P.

So, we're screwed here... looks like you won't be able to run your x16 @ x16... x12 at best.

But, x8 would be fast enough anyways, you might drop a frame.

Granted, this is still partially speculation and it might actually be able to turn off one of the x1 slots, and still run the x16 @ 16, even with your x8 in use.

You could always, you know... plug it in and find out...lol

Thank you for the in depth analysis. I have been running prime to test for stability (been flirting around 5ghz), but as soon as this run is finished I will swap slots and see what happens.

 

[m3ta1head]

Ended up modifying the case headers and moving the 7950 to the lower x16 slot, with the STX in one of the x1 slots above. However, after installing the card in the lower slot, it is reporting to be running at x8 v1.1 (according to GPU-Z). Not sure how this is possible, but after checking some benchmarks it appears that this will be noticeably detrimental to performance. Can anyone chime in and clarify what's going on here?

On the plus side, there's more breathing room now.

 

[Vectronic]

That lower x16 isn't a true x16... its an x8 with the length of a x16.

It never will run at x16, wasn't designed to, and is physically incapable of doing so.

The highest chance you have is your GPU where it was, and the STX in the slot the GPU is in now.

It will probably still run at x8 though, so really for cooling, you are probably better leaving it as is, but it's not difficult to test the other option.

 

[UaVaj]

7950/7970 needs 8gb/s of bandwidth (16x pcie 2.0 or 8x pcie 3.0)

(1) just like SLI/CF setup. top card always a little hotter. will be fine.
video in slot2. stx in slot4.

(2) grind down NH-D14 to fit.
stx in slot1. video in slot2

(3) (a)go with a smaller cpu cooler or (b) water cool cpu cooler or (c) different motherboard.

 

[m3ta1head]

Ended up going full circle and returning everything to their original positions. Remounted the D14 one final time, before carefully inserting the cards. I separated the sound card and D14 with a layer of ESD paper to ensure no shorts. All seems well now-the 7950 is running on a full speed bus and the sound card isn't shorting/producing any static from interference. I'm just going to leave it this way.

Click for high res version

 

[UaVaj]

keep in mind, the stx is right on top of the video. all that heat from the backside of the video is going right up to the stx. that is same effect in SLI/CF the top card is hotter.

the video is by design to take that extra heat, can the stx take the same heat?

 

[m3ta1head]

keep in mind, the stx is right on top of the video. all that heat from the backside of the video is going right up to the stx. that is same effect in SLI/CF the top card is hotter.

the video is by design to take that extra heat, can the stx take the same heat?

I've had the STX in the same position for over a year, with no problems so far. There is plenty of air moving over the components in the area, so there is no heat buildup. After returning the 7950/STX to the top slots, I've seen a 2-3C increase in GPU temps at load. CPU temps are exactly the same. Overall, my temps are excellent, so no complaints from me. Eventually, I'll buy a new mobo without PCI slots so I can install the STX at the bottom of the case.

 

[Foy]

Glad to see I'm not the only one having D14 clearance issues. I had to slightly bend the bottom three fins on one side because they wouldn't clear the Vengeance heat spreader on the inside stick. It wasn't much and nearly impossible to see even if you're looking for it.

I also had to ditch the 120mm fan on that side because if I moved it high enough to clear the RAM, it hit the side panel window . . . in an Antec Eleven Hundred, not exactly the smallest mid-tower case you can buy.

Even with just the 140mm fan, the D14 is a cooling beast. Better looking too, IMHO.

Foy