Foam shim on heatsinks

[StopSign]

Both my old Lanparty Ultra-D and my current Gigabyte 965P DS3 have this foam pad between the northbridge heatsink and the actual northbridge PCB. I've only seen this used for northbridge cooling because video cards don't this. Is the foam absolutely needed to protect whatever it's protecting on the northbridge PCB?

I ask this because I currently use a Noctua NC-U6 on my DS3. If you've seen the actual P965 PCB, there are lots of resistors and other stuff on top around the actual core. The NC-U6 came with one of those square foam shims but I had to cut it up and "strategically" place it around the resistors and stuff. Now I'm thinking of getting a P35 board and from the looks of it, the P35 PCB has even more crap around the core. I don't think cutting up some foam shim would do much good here.

Do any of you have northbridge coolers installed without the foam shim? From that I gather, it just relieves some pressure off the core so you don't accidentally crush it or something. But is that really necessary?

 

[BonzaiDuck]

That may be a pretty common thing: the foam shim around a NorthBridge core under the heatsink.

My understanding of it: it is there to keep the heatsink level and flat against the top of the tiny, square core component.

I replaced my ASUS aluminum chipset heatsink with the ThermalRight heatpipe alternative. And I cannot remember whether the TR cooler came with a foam shim. But in its narrowest dimension, it was not much wider than the square core itself, while the stock heatsink certainly was. So I'm thinking they put it there, in case the heatsink is moved off center, with the thought that the springs holding it in place may not be sufficient to keep the sink level and flat against the core.

 

[StopSign]

Originally posted by: BonzaiDuck
I replaced my ASUS aluminum chipset heatsink with the ThermalRight heatpipe alternative. And I cannot remember whether the TR cooler came with a foam shim. But in its narrowest dimension, it was not much wider than the square core itself, while the stock heatsink certainly was.

Same with the Noctua cooler. The stock shim on the DS3 is the size of the northbridge PCB itself so it just goes around the edges, while the Noctua shim is just large enough to go around the core, which doesn't fit with all the stuff around it.

Since you don't remember whether or not your Thermalright cooler came with a shim, would it be safe to assume that you didn't use a shim at all?

 

[BonzaiDuck]

Actually, I think there was a shim -- more of a black or charcoal-colored foam-rubber grommet with wax-paper backing.

I was really pleased with the TR chipset cooler, but I don't think I can use it on my new system (in progress) with the ASUS Striker board. I'd be better off replacing the TIM on the ASUS copper heatpipe "necklace."

I have a lot of work to do, and I've already put out feelers to reseller-tech-support-reps I know to get some more "skinny" on water-cooling parts and prices.

 

[RyanHirst]

Ha HA! (speed racer!). So I am *not* crazy (at least not for this reason)!

I, too, have the DS3. And the Noctua NC-U6. At this moment, I am doing two things:
1) typing
2) looking back and forth between the bare DS3 chipset (P965) and the Noctua foam spacer. DS3..... foam.... DS3.... foam.

Damnit.

Please excuse me while I use a few keywords to make sure that others with the same dilemma find this topic:

The foam spacer (shim) for the Nocuta NC-U6
... doesn't fit
... is the wrong size
... is too small
for standard Northbridge installation.

This is irritating. First, none of the reviewers mention it. I read three separate reviews for the product before buying. One went out of its way to praise the foam spacer. Which is too small.
Second, the P965 northbridge is not an unusual size. Maybe you start thinking, "well, maybe they're just being compatible with most northbridges...", because you remember how the northbridge used to be the size of the new southbridges.
Hopefully, your brain stops you: Wait a minute... it says. AMD motherboards don't HAVE a northbridge. So what other size would a new-to-market northbridge cooler possibly be designed for, if not the current Intel chipsets?
It is, I think, a fair question. (Besides, other current chipsets are the same size).

On the bright side, I've scritinized some review photos, and plenty of reviewers covering protruding transistors with the shim. For example:

http://www.hardware-mods.com/h...ewpage.php?page_id=133

It's a different cooler, but the same principle: on page 3 you can see close-ups of a shim being put over the protrusions of the Nvidia 650i chipset.

 

[RyanHirst]

Okay -- slightly OCD solution:

Using a knife or small screwdriver, remove foam shim from the stock DS3 Northbridge cooler. Center the NC-U6 on the foam spacer. The edges of the spacer stick out past the Noctua base, but you can just cut the protrusions off with an xacto knife. The resultant spacer is narrower than the original, but about the same width as the one included with NC-06.... and it doesn't sit on top of your transistors. Ta-daaa!

 

[StopSign]

The real question is: what purpose does the foam shim serve? Is it to prevent the heatsink from wobbling?

I don't think there would be any problems installing without the pad as long as you're careful.

 

[Old Hippie]

what purpose does the foam shim serve? Is it to prevent the heatsink from wobbling?

Asus support told me, it was to protect the components surrounding the chip.

 

[Navid]

Originally posted by: Old Hippie

what purpose does the foam shim serve? Is it to prevent the heatsink from wobbling?

Asus support told me, it was to protect the components surrounding the chip.

And that makes sense too.

Many chipset coolers use spring-loaded pushpins for installation. You could try to push the two pins at the same time. But, it is possible that someone may push one first and then push the other and that is the problem!

After you push one pin, the cooler will be tilted. Now, if you try to push the other, the sink will act as a lever putting pressure on the components surrounding the chipset. The pressure will be concentrated on the chipset itself after both pins are securely pushed. But, while you are lowering the second pin is when you could be damaging the components if there is no foam distributing the pressure.

Edit:
When you install a cooler with screws, you are supposed to gradually tighten the screws going from side to side.
You cannot do that with spring-loaded pushpins. They are either all the way in or out!
The only alternative is to push both pins at the same time. But, that is not always possible.