So as some of you know, I was asking about back plates for the 980s to give support to prevent sag.

What I was not expecting was the increase in fan whine after installing them on the cards.

Before the noise was low but tolerable. However, after installing the plates and remounting the cards the noise from the fans has increased dramatically.

Anyone else seen this. It's forced me to remove the cards and remove the back plates.

give them some cheese to go with the wine :D

seriously, some pictures would help to see what you are looking at.

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If they're the backing plates that I'm thinking of then they're really not good when being used on closely stacked GPU's as they do cut down the fans' access to the air needed to keep them cool (they have enough trouble getting enough air without them).

Cheers.

One question I have, Is it acoustic noise or increased fan speed causing this?

Do your fans run at higher speeds, or is it just noise from vibration?

Are they quiet when they first start up?

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it is acoustic noise from the fans.

When they first start up there is not much noise but as the cards heat up and the fans increase their speed, the noise gets louder.

I'm going to remove all of them and see if the noise goes down if so then I have the solution to my problem.

Wiggo, yes they probably are the ones you are thinking about.

http://www.newegg.com/Product/Product.aspx?Item=N82E16814998095&cm_re=backplate_980-_-14-998-095-_-Product

Assuming temps and fan speeds are roughly the same as they were, could it be the extra rigidity allowing more vibration to resonate into the PCIe slot mountings ?

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"Living by the wisdom of computer science doesn't sound so bad after all. And unlike most advice, it's backed up by proofs." -- Algorithms to live by: The computer science of human decisions.

Yea I can see how those placed closely to another GPUs fans could cause a whistle effect - lots of holes to create harmonics.

It should be fine to place one where you don't have a fan right up against it i.e. top card.

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I don't if it's good or bad that I can tear down these computers so fast, lol

Looks like Jason is correct.

I removed all the backplates from all 4 GPUs and now the whine is significantly decreased. Back to where it was before I tried this every expensive experiment :(

Well at least someone else will benefit from this.

If this computer was stuck off in a room by itself then the noise probably won't have been an issue but since it has to share my office, I really don't want any more headaches from that whine.

Thanks for all the advice everyone.

Zalster

Would rubber washers work as dampers on the vibration?

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I was thinking that to, a simple O-ring to dampen vibration.

But the purpose of the backplane seems to be to dissipate heat, isolating the heat transfer with rubber isn't a good idea. Better just to take it off and get what air you can.

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I was thinking that to, a simple O-ring to dampen vibration.

But the purpose of the backplane seems to be to dissipate heat, isolating the heat transfer with rubber isn't a good idea. Better just to take it off and get what air you can.

Hi Brent,
In actual fact they were obtained to prevent GPU sag AFAIR. The manuf's seem have designed them as a sort of aux heat sink, but that's not why he got em:-)

I still think sag 'might' be prevented by the use of plastic props to support the cards, not likely to generate any extra noise or impair air flow as the backplates did.

Regards,

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Cliff,
Been there, Done that, Still no damm T shirt!

Hi Zalster,

Looks like you're back with some sort of prop up system if you still intend to prevent GPU sag..

I still think plastic rod, of some sort, about .25" dia would do the trick, 'if' the GPU/Case layout permits..

Regards,

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Cliff,
Been there, Done that, Still no damm T shirt!

Reducing card sag is a result of putting more metal on it?

It's an extra heatsink designed for just that. It's gong to make the card heavier, with no added support.

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Hi Brent,
The basic idea was/is to stiffen up the card so that extra support is given by the backplane and the screws at the case slot...

Some GPU's are sold with a backplane from the manuf's for exactly that reason, not to add extra heat dissipation, but to add support to the card pcb.

When the card is screwed into a case it provides extra support to the GPU, and most high end cards are double slot thickness, so there are 2 case screws to hold the card with a ridged backplane in place.

Where things tend to fall apart is that there are seemingly NO motherboard manuf's that actually make motherboards with sufficient space between the pcie x16 slots to allow cooling space:-( And if there was a mobo made that did that, then there would be a case slot problem anyway:-( ie getting such a mobo pcie x 16 slot to match the case slot openings..

The best possible resolution to GPU heat is for NV & AMD to make GPU's that only occupy 1 slot width, or at most 1.5 slot width. And to do that they would have to reduce the power consumption drastically.

Which they aint doing, the reverse in fact with GPU's with a shed load of additional memory and needing 2 aux power connectors to work.

Regards,

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Cliff,
Been there, Done that, Still no damm T shirt!

Hey Brent,

Cliff is right. Originally I got them to see if they could be used to prevent GPU sag.

A secondary benefit would have been a small decrease in temperature of the GPU.

Unfortunately, as Jason pointed out, they seemed to have caused some Harmonic resonance with the Fans and MoBo that caused an terrible howling sound.

After I removed them, the sound went away.

I guess they are better suited for single or max dual GPU config as opposed to my 4 GPU config. :(

Live and learn.


Zalster

Zalster, have you thought about using a nylon/plastic all threaded rod with some nuts and washers (of the same material as the rod) to support those cards?

Cheers.

Wiggo,

I'm waiting on that rod that I ordered from Moddiy to see how that works out

We had an interesting discovery on our units concerning noise and fans. If you have something that disrupts the smooth flow of air such as vent holes near the fans, they will whine. The closer the air disruption to the fan, the more racket the fans will make. If you can, get the fans in the open air or pull any safety grill work off the fan that should help. Because our design was fix, we couldn't change out the the grill to something more open but our customers don't care much because our units are installed in a room where our unit is one of many making racket and the tape monkey is about the only one in the room.

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our customers don't care much because our units are installed in a room where our unit is one of many making racket and the tape monkey is about the only one in the room

Why isn't that included in the features listed with the backpane? LOL

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our customers don't care much because our units are installed in a room where our unit is one of many making racket and the tape monkey is about the only one in the room

Why isn't that included in the features listed with the backpane? LOL

Our unit connects to a mainframe and can have up to 70 processors in 2 feet of rack space. It's a form of communication processor/protocol converter that handles up to 256 lines and is nothing like a PC.

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