Accelero Xtreme GTX 280 mini review and support

[OnBoard]

I bent the neighboring fins back to give me some room to work but the channel is still too steep to get the cutting wheel in at a useful angle. In the end I just bent the fin back and forth and it popped off very smoothly...used needlenose pliers with the nose right at the bottom of the fin and moved back and forth along the fin with a couple of bends at each point to get a clean break. I finished with a small file to clean up the bottom and then bent the neighbors back into place.

Bending is good way to break off fins, if there is room. Did that with NVIO chip for couple fins that needed to go for new holes. My pliers are just quite thick in the end, so that option didn't come to mind

I'll probably add some support wires to hold some of the weight of the video card just to be safe...that's a lot of metal hanging off the end and there's no backplate on the GTX 275.

Yes, that would be smart. Had my card end also hanging with a "wire" (those black things that come wrapped around wires, with mouse, fans & stuff). HDD cage was near there on previous case. Might put a support wire on this new one too, even though I have a backplate.

One of my earlier plans for this build was heat pipes on the memory and NVIO chips as well, with some/all of them connecting to the Accelero. That spot you point out was one of the places I considered attaching them (the top/bottom faces of the fins were also possible). Unfortunately there would be a lot more work in attaching heat pipes between the video card and the Accelero...assuming you don't want to permanently mount the cooler, that is.

I though about same thing after I saw what you did.

http://www.quietpc.com/fi-en-eur/products/fanless/hfx-527

That sort of stuff would be great for sticking a pipe from VRM to the Accelero cooler base end. Pity that it's so expensive. That mount part with some paste would obviously be needed, not to be a permanent mount. Unless you want to take the VRM cooler part off too every time you need to take Accelero off.

I think I have a passive Zalman cooler (this http://www.xbitlabs.com/articles/video/display/zalman-zm80d-hp_3.html) somewhere, that would have sort of the mount needed to attach the pipe to Accelero in non permanent solution.

Would be a lot of work though and I'm more worried of ruining the stock VRM sink part, as I have no backup, if things go wrong. But it's still a tempting idea, as Accelero has so much cooling power left in it for more than core.

 

[mudkip]

Bending is good way to break off fins, if there is room. Did that with NVIO chip for couple fins that needed to go for new holes. My pliers are just quite thick in the end, so that option didn't come to mind



Yes, that would be smart. Had my card end also hanging with a "wire" (those black things that come wrapped around wires, with mouse, fans & stuff). HDD cage was near there on previous case. Might put a support wire on this new one too, even though I have a backplate.



I though about same thing after I saw what you did.

http://www.quietpc.com/fi-en-eur/products/fanless/hfx-527

That sort of stuff would be great for sticking a pipe from VRM to the Accelero cooler base end. Pity that it's so expensive. That mount part with some paste would obviously be needed, not to be a permanent mount. Unless you want to take the VRM cooler part off too every time you need to take Accelero off.

I think I have a passive Zalman cooler (this http://www.xbitlabs.com/articles/video/display/zalman-zm80d-hp_3.html) somewhere, that would have sort of the mount needed to attach the pipe to Accelero in non permanent solution.

Would be a lot of work though and I'm more worried of ruining the stock VRM sink part, as I have no backup, if things go wrong. But it's still a tempting idea, as Accelero has so much cooling power left in it for more than core.

Buy another stock cooler

 

[undetermined]

Just an update for those people who are curious. I've been trying to get an SLi rig up with the GTX280s I have. Honestly, things just get too hot with the Accelero in there if you're using SLi. Unless you can put a good gap in between the Accelero and the card below it you're going to see massive temp gains. I'm talking almost to stock levels. I'm actually about to remount my stock cooler to the card that has the Accelero and just run them both stock until I can come up with something different.

Anyone know a good place to start if I want to water cool these cards? Any help would be greatly appreciated.

 

[Daleraith]

Been following this thread for a while and joined the forums because I'll start 'cutting' in a week or two

The cooler's just a paperweight until the other bits are sorted and now I've been looking at the D-Tek Uni-Sink solution suggested by Retro. Finally found an Australian site that stocks them - on special at AU$35 (at the time of this post).
The graphic was down on the site but the description matched other (US) sites, so it's now on order (fingers crossed the description was correct)
For anyone that's in Oz:
http://www.gammods.com.au/store/index.php?main_page=product_info&products_id=1195

 

[Retro*]

Been following this thread for a while and joined the forums because I'll start 'cutting' in a week or two

The cooler's just a paperweight until the other bits are sorted and now I've been looking at the D-Tek Uni-Sink solution suggested by Retro. Finally found an Australian site that stocks them - on special at AU$35 (at the time of this post).
The graphic was down on the site but the description matched other (US) sites, so it's now on order (fingers crossed the description was correct)
For anyone that's in Oz:
http://www.gammods.com.au/store/index.php?main_page=product_info&products_id=1195

Good luck with the Uni-Sink. I haven't done anything with mine because I am upgrading a system for a friend who wants my 280 (less the Uni-Sink) So I am now running a stock cooler-equipped 275 that I picked up for a good sale price.
OnBoard posted some excellent cutting options for the Uni-Sink.
Keep us posted on your project!

 

[b1k3rdude]

Ive been keeping an eye on this thread since learning about the VRM heat issue, which luckily I found out about before lashing out £45 on the Accelero...

Im leaning toward the uni-sink aproach and have been looking for peoiple who have modded it and came accross this - http://www.linustechtips.com/build-logs/using-a-d-tek-uni-sink-with-an-mcw60. Its not what we need but it gives us more info on the uni-sink etc.

Just sent an email to AC Switzerland, HongKong and USA...

Hello

I have been and AC fan/customer for many years, the last product i bought was the AE-GTX8800, but I have to say I am quite disappointed by your latest product! As detailed in the thread below (and many others via google), the VRM heatsink provided with the Accelero Extreme GTX280 is clearly not fit for use as indicated by the 138c temps...!!!!!! and in all likelihood will damage customers cards in the longterm.

http://forums.techpowerup.com/showthread.php?t=89018 -

I have been looking for alternatives to the AC VRM heatsink provided, but why should I have to do this after spending £50 on your cooler! Galaxy(and others) who use your cooler on their card/s have used a proper heatsink on the VRM's, they have seen the obvious flaw and if they can why cant AC?!....

So I urgently ask, please change the cheap aluminum 'heatsink' so that:-

1. its more substantial, thicker with more cooling fins on.
2. its retained to the card by spring clips and not the cheap double sided sticky pads(these are part of the problem).

Also the backplate provided with the is utterly usless:-

1. doesn't sufficiently cool the back of the card and the memory chips,(using those cheap double sided sticky pads again...)
2. because its so flimsy it allows the card to bend when the main heatsink is installed.

Customers are better advised to re-use the original backplate as it doesn't suffer from the above 2 points!

regards

A disappointed long standing customer.

 

[OnBoard]

Been following this thread for a while and joined the forums because I'll start 'cutting' in a week or two

The cooler's just a paperweight until the other bits are sorted and now I've been looking at the D-Tek Uni-Sink solution suggested by Retro. Finally found an Australian site that stocks them - on special at AU$35 (at the time of this post).
The graphic was down on the site but the description matched other (US) sites, so it's now on order (fingers crossed the description was correct)

Good luck with the Uni-Sink. I haven't done anything with mine because I am upgrading a system for a friend who wants my 280 (less the Uni-Sink) So I am now running a stock cooler-equipped 275 that I picked up for a good sale price.
OnBoard posted some excellent cutting options for the Uni-Sink.
Keep us posted on your project!

Ive been keeping an eye on this thread since learning about the VRM heat issue, which luckily I found out about before lashing out £45 on the Accelero...

Im leaning toward the uni-sink aproach and have been looking for peoiple who have modded it and came accross this - http://www.linustechtips.com/build-logs/using-a-d-tek-uni-sink-with-an-mcw60. Its not what we need but it gives us more info on the uni-sink etc.

Just sent an email to AC Switzerland, HongKong and USA...

Nice mail I was planning on mailing them back when I started this, but never got to it.

And combined response to all of you. Now that the VRM temps came up again I might as well tell my current plans for it. After Donovan posted those heatpipe cooled pictures I was itching to do something similar, but I didn't have any heatpipes laying around, nor did I find anything suitable for reasonable price.

So I finally settled for a heatpipe RAM cooler, as those have fins ready on the other end and need "just" the heatpipe attached to the VRM plate. I went for this one, as it is thin and it was on sale
http://www.thermaltake.com/product/Cooler/VGAnCHIPnMEM/Memory_cooler/cl-r0026/cl-r0026.asp

Then I got some thermalpads to fill up the order and this one (Thermalpad 3mm (100x20mm) is planned to go behind the VRMs under the backplate.

http://specialtech.co.uk/spshop/customer/product.php?productid=9699&cat=0&page=1

Hopefully it's the right thickness, should work from 1.5-3mm and provide some extra cooling to VRMs.

Not 100% sure yet how I'll mount the heatpipe and where I'll position the fins, have to have in hand first. One idea would be however to cut the middle top of the cooler (post #549) and then position the fins of the heatpipe under it.

Don't know if the parts come this week or next, but I'll post more then

 

[b1k3rdude]

Nice mail I was planning on mailing them back when I started this, but never got to it.

Thermalpad 3mm (100x20mm) is planned to go behind the VRMs under the backplate.

Thanks, hopefully I get a positive response - as in they are gonna do something about it.

I pulled my GTX280 apart to see what pads/paste could be replaced and the have had the following results..

Idle........................................................................ Load................................................................

I removed the thermal pads from the VRMs but left it on the memory and the bridge chip.

So the AS5 works well on the VRMs but something has gone very wrong with the GPU. I have double checked and the AS5 is covering all of the Gpu area and making good contact. The only thing I can think of is because I was very low on AS5 I used a solvent to thin it out a bit and this has contaminated the AS5...?? what say you lot..?

I have ordered a tube of 'OCZ freeze' its easy to apply, no cure time and wich got a 'A' in the 80way testand some new thermal pads, because the above situation has to be resolved.

.

 

[mudkip]

Thanks, hopefully I get a positive response - as in they are gonna do something about it.

I pulled my GTX280 apart to see what pads/paste could be replaced and the have had the following results..

Idle........................................................................ Load................................................................
http://img17.imageshack.us/img17/6027/gtx280as5vrmas5mempadsi.jpghttp://img17.imageshack.us/img17/7590/gtx280as5vrmas5mempadsl.jpg


I removed the thermal pads from the VRMs but left it on the memory and the bridge chip.

So the AS5 works well on the VRMs but something has gone very wrong with the GPU. I have double checked and the AS5 is covering all of the Gpu area and making good contact. The only thing I can think of is because I was very low on AS5 I used a solvent to thin it out a bit and this has contaminated the AS5...?? what say you lot..?

I have ordered a tube of 'OCZ freeze' its easy to apply, no cure time and wich got a 'A' in the 80way testand some new thermal pads, because the above situation has to be resolved.

.

kinda bad temps , my modded stock cooler did much better. especially on load

http://forums.techpowerup.com/showpost.php?p=1331287&postcount=52

 

[OnBoard]

I removed the thermal pads from the VRMs but left it on the memory and the bridge chip.

So the AS5 works well on the VRMs but something has gone very wrong with the GPU. I have double checked and the AS5 is covering all of the Gpu area and making good contact. The only thing I can think of is because I was very low on AS5 I used a solvent to thin it out a bit and this has contaminated the AS5...?? what say you lot..?

I have ordered a tube of 'OCZ freeze' its easy to apply, no cure time and wich got a 'A' in the 80way testand some new thermal pads, because the above situation has to be resolved.

AS5 on VRM is a bad idea, all it needs is a little drop somewhere on the wrong place and things could go horribly wrong. The card is still working, so obviously it's just in right places, but I wouldn't use it there.

OCZ Freeze is "Non-electrically conductive" so that would be ok for VRM, although it seems kinda thin, if thick layer is needed.

Thinner might have done something funky to AS5 core doesn't go that high even on stock paste and that stuff was in there thick. Just clean everything and apply the new paste once you get it and let's hope everything is good again.

 

[b1k3rdude]

kinda bad temps , my modded stock cooler did much better. especially on load. http://forums.techpowerup.com/showpost.php?p=1331287&postcount=52

Yeah Im leaning towards that untill AC sort their act out with the AE.

• The card is still working, so obviously it's just in right places, but I wouldn't use it there.
• OCZ Freeze is "Non-electrically conductive" so that would be ok for VRM, although it seems kinda thin, if thick layer is needed.
• Thinner might have done something funky to AS5

yeah, I was aware so I put a little smudge of it on each of the VRM's, but it goes to show that the original thermal pads werent doing their job very well.

I`ll see when I get it, all the places that reviewed it said it was as sticky as AC5.

Cool, but the only way to be sure is when the OCZ stuff arrives

 

[OnBoard]

I`ll see when I get it, all the places that reviewed it said it was as sticky as AC5.

Yeah, It'll work fine. I just looked at these pictures, seemed a bit liquidy
http://www.ocia.net/reviews/oczfreeze/page2.shtml

"The consistency of Freeze can be described as having much less viscosity than Arctic Silver 5. This allows for much easier application, which can contribute to a better spread of the paste on the CPU."

Though my AS5 is no where near as thins as on this second picture (years old tube)
http://www.mikhailtech.com/Reviews/OCZ_Technology/Freeze_Thermal_Compound/page2

Noctua NT-H1 that I stick to my VRMs you could make a tall tower of it

 

[b1k3rdude]

yeah, I was aware so I put a little smudge of it on each of the VRM's, but it goes to show that the original thermal pads weren't doing their job very well

As I had some spare time this evening, I took the GTX apart again and very carefully and thoroughly cleaned of all the AS5 and Just for comparisons sake I applied some generic thermal paste(evercool-420) to the VRMs and the GPU that I had laying around and the result was disappointing... The VRMs are running a little hotter which as expected, but the GPU is still tanking at 110c with only 1min via furmark.......

Im a computer engineer, so i am not ham fisted, but I'm grasping at straws here... Is it possible I have 'somehow' damaged the heatpipe(by just taking the cooler off..?!) or over tightened the 4x screws on the GPU causing the contact between the GPu and the heat-spreader to be less than optimal (I checked the Paste pattern with the AS5/Evercool, and there has always been a good contact patch)

I lowered the clocks in Rivatuner which made no dif to the load temp, lowering the 3d voltage helped a tinny bit but it just prolonged the rise to 110c+..... I would like to find out exactly what is causing the high GPU temp, because its doing my bloody head in. If I had a spare cooler I could rule that out...

 

[Retro*]

Wow!
This thread is just aging like a fine wine
OnBoard, I cannot thank you enough for all your hard work here
Although I have made a strange move and gone to a stock-cooled GTX 275, I still have plans for some cooling improvements on my new card and it doesn't include Thermalright Arctic Cooling is an old friend to me, they did wonders for cooling a few *cough* ATI* cards I did a few years ago. The Accelero is on my list now, in spite of the "problem child" GTX 275 thingy that resides by the NVIO chip. That's easily cured with a Dremel
If the postage/shipping charges to Finland were reasonable, I would gladly send my D-Tek Uni-Sink to you just to play with

Unfortunately, I have other reasons for abandoning the Uni-Sink with my (former) 280. I think I may have screwed-up my TR HR-03GTX by "crimping" the heatpipes too much. There was some kind of fluid leaking out of one or more heatpipes onto my counter when I crimped them to try to clear the Uni-Sink. So, when I was offered cash for my GTX 280, I went for it. The option of buying a replacement TR-HR-03GTX didn't even cross my mind
Sent a few pics of my current cheapo paste mod to tie me over until I buy an Accelero.
I do like their choice of thermal pads that has replaced the weird, gauze pads that came with my 280.
Before:

Original Nvidia sweatshop paste job:

After cleaning and some AC MX2 applied: Whoops, forgot to clean out the screws

Helps the temps a bit, but nothing like a good cooler does.
As for my VRM temps, Nvidia was smart to remove the register for that on the 275. (Conspiracy Theory)

I agree that Arctic Silver is a bad choice for video cards. I quit using it years ago, AC MX2 is my current paste of choice.
OnBoard: Great idea with the Thermaltake ram coolers. You just don't give up, do you?

b1k3rdude: Good for you to send that info to AC. I hope to see a real, qualified answer to that. But, I have sent some heated, but non-threatening e-mails to Thermalright a few times, about their equally weak vrm cooling solutions, they only reply in very generic terms, like "Don't use FirMark!"
OK. I will just play "Spider Solitaire", no stress on the card. Idiots.
And so it goes.

 

[OnBoard]

As I had some spare time this evening, I took the GTX apart again and very carefully and thoroughly cleaned of all the AS5 and Just for comparisons sake I applied some generic thermal paste(evercool-420) to the VRMs and the GPU that I had laying around and the result was disappointing... The VRMs are running a little hotter which as expected, but the GPU is still tanking at 110c with only 1min via furmark.......

Im a computer engineer, so i am not ham fisted, but I'm grasping at straws here... Is it possible I have 'somehow' damaged the heatpipe(by just taking the cooler off..?!) or over tightened the 4x screws on the GPU causing the contact between the GPu and the heat-spreader to be less than optimal (I checked the Paste pattern with the AS5/Evercool, and there has always been a good contact patch)

I lowered the clocks in Rivatuner which made no dif to the load temp, lowering the 3d voltage helped a tinny bit but it just prolonged the rise to 110c+..... I would like to find out exactly what is causing the high GPU temp, because its doing my bloody head in. If I had a spare cooler I could rule that out...

Hmm, that doesn't sound right at all. What temp was GPU hitting before you took the cooler off? There were some GTX 280 cards that hit almost instant 100C+ temps in past, but those were new cards. Surely that sort of thing just doesn't happen.

Screws shouldn't cause any issues, as they just stop when they bottom out the springs and then being so tiny any serious force is hard to come by.

Is the fan still ramping up? That GPU-Z screenshot seemed to show 100% speed and plenty RPM, so guess it is. Spare cooler would indeed help at this point. I'm grasping at straws here too, but maybe a dustdog has jumped and blocked airflow in the cooler fins? That's what we call our little furry pets here in Finland

I'd suggest you remove the plastic shroud and check if it needs cleaning. If the contact is good then heat should be getting to the cooler, but maybe not out. I know it'll be a paint to dismantle it once again, but 120C should be the throttle limit on the card, probably not getting there with games yet though.

 

[b1k3rdude]

• Hmm, that doesn't sound right at all. What temp was GPU hitting before you took the cooler off?
• Is the fan still ramping up?
• but maybe a dustdog has jumped and blocked airflow in the cooler fins?

• It was not getting higher than 85c in games/3dmark, stupidly I never testing it with furmark before dismantling it(now im regretting touching the damn thing at all...)
• yup, it goes right upto 100% as the GPu temp just rockets upto 104c almost instantly.
• nope, the fine are very clean and free of dust bunnies.

 

[OnBoard]

Wow! This thread is just aging like a fine wine
OnBoard, I cannot thank you enough for all your hard work here

Thanks

If the postage/shipping charges to Finland were reasonable, I would gladly send my D-Tek Uni-Sink to you just to play with
OnBoard: Great idea with the Thermaltake ram coolers. You just don't give up, do you?

VRM temps are now OK with lowered voltage and my new spinning up cooler, but few degrees lower wouldn't hurt Yeah, I might have wanted that before I ordered the heatpipe thing. Air mail is pretty cheap, have ordered some guitar strings from US, but that sink weighs a bit more I was even thinking of wanting the TR-Enzo plate, when you were going to Uni-Sink. Unless you cut the middle portion of the Uni-Sink, that would bring the weight down

Unfortunately, I have other reasons for abandoning the Uni-Sink with my (former) 280. I think I may have screwed-up my TR HR-03GTX by "crimping" the heatpipes too much. There was some kind of fluid leaking out of one or more heatpipes onto my counter when I crimped them to try to clear the Uni-Sink. So, when I was offered cash for my GTX 280, I went for it. The option of buying a replacement TR-HR-03GTX didn't even cross my mind

Ouch poor TR. Surely it'll work fine with 5 pipes too

Sent a few pics of my current cheapo paste mod to tie me over until I buy an Accelero.
I do like their choice of thermal pads that has replaced the weird, gauze pads that came with my 280.
Helps the temps a bit, but nothing like a good cooler does.
As for my VRM temps, Nvidia was smart to remove the register for that on the 275. (Conspiracy Theory)

I'm liking those thermal pads, much better (to work with) than those white fiber thing. Those look pretty similar to what AC has bundled with the cooler, or maybe they are this sort of stuff?
http://www.aquatuning.de/product_in...malpad-Ultra-5W-mk-100x100x1mm--1-piece-.html
http://www.aquatuning.de/product_in...--for-ramplex--innovatek--Mips--Koolance.html

The purble ones (that I have coming) are 1.5W/mK. No idea what that mK stands for. Or is it something like milliKelvin that wouldn't make sense though

And good luck with the GTX 275 Accelero, hope you find the cooler cheap

 

[OnBoard]

• It was not getting higher than 85c in games/3dmark, stupidly I never testing it with furmark before dismantling it(no im regretting touch the damn thing at all...)
• yup, it goes right upto 100% as the GPu temp just rockets upto 104c almost instantly.
• nope, the fine are very clean and free of dust bunnies.

Dust bunnies! now that you said the work I remembered it. That's a straight translation of your dogs, but even cuter

Maybe you should try with 3DMark/games now too? Could be just that you core runs a bit hotter. Nothing that Accelero wouldn't fix then. That Instant rise though doesn't sound good :/

 

[b1k3rdude]

Maybe you should try with 3DMark/games now too? Could be just that you core runs a bit hotter. Nothing that Accelero wouldn't fix then. That Instant rise though doesn't sound good :/

Done that, im getting an instant rise with every 3D app. I have raised an RMA but have hard to order some new memory pads (the card has been apart 4 times now) and replace these before it goes back.

 

[undetermined]

Done that, im getting an instant rise with every 3D app. I have raised an RMA but have hard to order some new memory pads (the card has been apart 4 times now) and replace these before it goes back.

If you thinned out the AS5 you might have made a really rough move. I am using AS5 as my replacement after putting the stock cooler back on and I've not had any issues. The way I did it was putting a really big glob in the center of the cooler. If you use too little it won't be enough.

Some GTX280s had that issue where they insta-jumped a ton of degrees and for some people the issue just randomly showed up one day. RMAing sounds like the best bet if you can get it through.

Also, I believe that removing the VRM registers was definitely a conscious move on their part to help out their vendors. There's no way that it makes the card any more efficient or even that much cheaper to produce, it just doesn't allow us to all freak out over how hot the VRMs are getting.

 

[b1k3rdude]

Also, I believe that removing the VRM registers was definitely a conscious move on their part to help out their vendors. There's no way that it makes the card any more efficient or even that much cheaper to produce, it just doesn't allow us to all freak out over how hot the VRMs are getting.

eh I dont understand..?

 

[OnBoard]

As for my VRM temps, Nvidia was smart to remove the register for that on the 275. (Conspiracy Theory)

Also, I believe that removing the VRM registers was definitely a conscious move on their part to help out their vendors. There's no way that it makes the card any more efficient or even that much cheaper to produce, it just doesn't allow us to all freak out over how hot the VRMs are getting.

eh I dont understand..?

Probably a reply to that. No voltage control chip, that also monitored the VRM temperatures in the 65nm cards, in the 55nm versions.

------

Your item, posted on 01/09/09 with reference xxx has been passed to the overseas postal service for delivery in FINLAND. Whii

 

[b1k3rdude]

Ok Ive made some progress...

The issue is subtle to be sure, but I now believe the thermal paste wasnt thick enough so wasn't evenly spreading across the whole surface of the gpu. The load temp isnt rising as quickly as before but its still reaching 104c, which means the HS still isnt sitting correctly on the GPU...

Hopefully it's the right thickness, should work from 1.5-3mm and provide some extra cooling to VRMs.

Just to let you know that 1mm is far too THICK on my GTX280. The GPU is unable to make full contact. So as it has to be less than less than 1mm, so am buying the only stuff we can get under 1mm which is 0.5mm. Order today will be here either Sat or Mon.

 

[ethox]

This review was a lifesaver, you might recall my problem in this thread.

In my 4 day long project (don't laugh, I do have to make a living ), I did exactly as OnBoard did in the review posts, hacksawed my way trough, and I thought I'd post some updates. I also had to modify my Antec Sonata III by sawing off 2 of the bottom hard disk spaces, since the cooler was too big to fit in the case.

This one is with 3 mins of furmark

This one is idle, 3 mins after stress

I do have one problem though, the upper RAM-heatsink doesn't stick at all, and I'm wondering how glue behaves in those temperatures.

I'd like to thank OnBoard and other posters in this thread for the great methods you decided to share. I would've also posted pictures about the project if my camera would work.

 

[b1k3rdude]

I do have one problem though, the upper RAM-heatsink doesn't stick at all, and I'm wondering how glue behaves in those temperatures.

That sound like the thermal double sided tape is faulty, you could email AC, but to be honest that may take ages. ChilledPC sell the same stuff for a few quid, just replace the tape on the back of the ramsink and you should be fine.