noob questions - fitting a GPU cooler

[GaryRW]

OK - I've got a reasonable bit of experience building and tinkering with computers, but have only swapped out heatsinks a few times, and never a GPU cooler.

I'm planning on replacing the stock cooler on a sapphire 6870 (reference as far as I know) with an Arctic cooling Accelero Twin Turbo Pro (http://www.arctic.ac/en/p/cooling/vg...ro.html?c=2182). Stock cooler is just a bit too loud for my liking, and in a P182 the temps are a little bit high too.

Now, what concerns me is the VRM and ram. It's not clear on the new website, but Arctic cooling recommends different heatsinks for the 6870 (http://www.arctic.ac/en/p/cooling/sp...114/vr001.html). I'm not entirely sure how these are different to the ones that came with the cooler - maybe more, or they're slightly bigger??

My plan though is to reuse the metal baseplate from the stock cooler. This pic (http://www.atomicmpc.com.au/Gallery/...-guide.aspx/27) and description would suggest you could take off the stock cooler (+ fan I hope) and just leave the base plate on for cooling the ram and VRM's.

So, the noob questions are:

1. I take it you use the same thermal paste as with CPU's? (The cooler has got paste pre-applied, but looks pretty thick to me...)
2. Can I resuse the thermal pads from the stock cooler metal base plate, or would I need to replace those with new pads? - You can see the thermal pads I'm talking about on that pic
3. If I re-use the pads, should I stick thermal paste between or will that mean they won't stick? Or would screwing the base plate back on be enough for contact?
4. What part of the cooling circuitry actually needs cooling? I think the mosfets are the low chips, and the chokes (?) are the taller grey boxes. The arctic cooling instructions suggest sticking heat sinks on all of them, but looking at the same pic as above, the stock base plate only attaches to the lower chips
5. Any general hints and tips? I'm planning on lowering the frequencies as far as possible in CCC before I try this, and then slowly increasing them after I've swapped the cooler out.

From reading around, looks like VRM cooling was a big issue on the 5870, but VRM temps I'm getting are much lower - about 47c on idle, up to about 55c after 30mins gaming. That's at stock frequencies. I may overclock, but won't be messing around trying to increase voltages.

Anyway, any comments or answers to the above would be great. Feeling a bit nervous about killing my new card

[nibbler]

1. Yup, use any thermal paste
2. Not recommended AFAIk
4. Put the little RAM sinks in as many places as possible, can't do any harm.

[Pob255]

With the way the 6870 stock cooler comes apart http://www.atomicmpc.com.au/Gallery/...-guide.aspx/27 it may be possible to remove the blower from the aluminium base plate that forms the cooler for the memory and power circuitry.
edit: yes you can remove the fan from the base plate http://www.atomicmpc.com.au/Gallery/...-guide.aspx/26
going through those pictures, it's looks like it's fairly easy to take the cooler apart and reuse the base plate.


If not then you are going to have to add heatsinks to the memory chips and power circuitry, which bits need cooling will be fairly easy to tell, when you take off the base plate every bit that's connected to it via thermal pads will need a heat sink.

Thermal pads can be reused however they are not sticky and don't support weight, heat sinks normally come with thermal double sided tape applied to them which is how they are held on.
You need to make sure that any thing that had a thermal pad touching it is fully cleaned (get some Isopropanol http://shop.ebay.co.uk/i.html?_trkpa...&_sop=15&_sc=1 for cleaning off residue) because the thermal pads leave an oily residue to which the tape will not stick correctly, it'll be fine at first but after about a month you'll find the heat sinks will drop off.

[GaryRW]

Thanks for the replies. I've seen others who have applied the little heat sinks that come with the GPU cooler to the back of the metal stock back plate about where the ram is - as you say nibbler, can't hurt

Pob255 - not sure whether you're saying re-using the thermal pads would be ok if I'm able to use the stock metal plate?

But if re-using the thermal pads is a bad idea - any recommendations as to where to buy some and how thick it should be? Looking on e.g. chilled pc (http://www.chilledpc.co.uk/shop/inde...940ee207244df1), there seems a massive range of thickness's. I can't tell from the pictures how deep/thick the existing pads are likely to be. Is it too simplistic to say go for the thick 5mm and let it be squashed down (it looks squidgy stuff )

thanks again

[Pob255]

not sure whether you're saying re-using the thermal pads would be ok if I'm able to use the stock metal plate?

Sorry should of been clearer, they are not that old so yes it should be fine to reuse the pads if you reuse the plate.
Just try not to touch them or generally contaminate them.

I though you meant using the pads to attach heatsinks.

[GaryRW]

OK - I finally got around to fitting the AC Accelero Twin Turbo Pro last night.

To answer my own question in case any one comes across this on google - no, you can't use the metal back plate from the stock heatsink/fan. Unfortunately the heatpipes from the Accelero get in the way. So I just used the standard heatsinks that come with it for the ram and vreg / vrm's.

The temps I'm getting are about the same to be honest - a bit lower but not staggeringly. It's a lot quieter though - it's now inaudible against the other fans in the system unless I force it to 100%, and even then it's only marginally louder.

I'm getting VRM temps of about 60c after a good hour of gaming - can anybody say whether they're ok or not??