alphacool eisblock rtx 4080 reference temperature issue

[Mr Mcgoo]

So i purchased this block from another uk site for my inno3d rtx 4080 super x3, for which it is listed compatible. However, after 3 repastes, I have the same temperature issue of 62c gpu 74c hotspot after full loop saturation with 33.5c water temps and 1500rpm fan speed. I have used all the provided thermal paste and even used another rather expensive thermal paste after the third try and the temps remained the same. Others using the same gpu and block combo are getting far better temps. Could I have an issue?

 

[Mr Mcgoo]

I have in fact just contacted them but just checking if anyone here has had the same or similar issues regarding this block or anyblock from alphacool and the rtx 4080/super

 

[Mr Mcgoo]

I've only used one alphacool block but it was for a 3080ti. No complaints though and the instructions were pretty good.

33 coolant temp sounds reasonable but have you double checked that the flow through the block is going in the right direction? That might make a bit of a difference.

coolant temp is great and flow is correct. can't get that wrong due to the block having flow indicators directly on it lol. when i did a repaste i did notice very tall peaks which would indicate poor contact on the die. so likely the thermal pads i was supplied with are wrong/too thick?

 

[Mr Mcgoo]

Tall peaks in the paste? I would think that's more to do with how much you've used and how you've taken the block off.

If you applied a small blob in the middle and the paste spread out to the far edges then the contact should be fine. If it's not getting out that far then that might be a pressure issue. There's no easy way to empirically test it, the best I can think of is to take all the thermal pads off and see if there's any difference in the spread of the paste.

By tall peaks i mean nothing had pushed to the edges and the paste was maybe not making full contact. I just tried the small blob method last night and that was a bad idea as temps hit 80c instantly under 320watt load. Paste hadn't fully spread. Nothing on the edges were covered and the blob in the middle was still thick as if it had not spread fully. This makes me think i do have a contact issue.

 

[Mr Mcgoo]

Sounds like the thermal pads are too thick.

Just to see if it is the pads causing the issue
Take off all the thermal pads and reassemble with just a small blob of paste in the centre.
Obviously DO NOT run it like this, just immediately dissasemble to see if you have good paste coverage. ie its "squished" out evenly

Weird that you mention trying without thermal pads. i did this at 9.30 this morning and just finished my testing. However, last night i went back to the stock air cooler (for testing) which gave me the same gpu temp but 5c lower hotspot. This morning i went back to my block and tried without the vram pads and i got much better spread. I very quickly tested with furmark and kept a very close eye on the vram temps. thankfully the vram temps only hit 82c but the gpu hit 51.3c and hotspot 60.8c. 26.5c ambient room 0.5c lower than last night and 36.9c water temp 3.5c up from last night. A ten 10c drop in temps with the increased water temps proves i have the incorrect vram thermal pads. I disassembled the block put the pads back on and temps went back to the same as before the pads were removed. Now alphacool got back to me and asked for pics of the pad imprints and paste spread/contact and stupid me forgot to take a few pics and i really CBA to take it apart for the 7th time. i just hope alphacool send out the correct size pads which from my research is incorrectly 1mm and others have had 0.75mm vram thermal pads sent out to them after they to found out the same temps issues was caused by the incorrect vram pads.

 

[Mr Mcgoo]

waiting on a reply from alphacool. As the issue is vram thermal pad being the incorrect size, it should be up to alphacool to fix. only time will tell

 

[Mr Mcgoo]

Disappointing that you were sent the wrong pads but glad to hear you've figured it out. I'm sure alphacool will sort you out if it's an issue others have encountered before.

alphacool have replied and said without photos they can't help and i really can't be bothered to take the block off again. In my reply i mentioned others that had a similar issue that was fixed by you sending out 0.75mm vram pads. is it possible for replacement pads otherwise i will have to return the block as faulty for refund? not just waiting for a response.

If they’re less than 3mm thermal putty is also another option. Better temps and more squishy so no contact or sizing issues.

i have thought about this but decided against as others have had issues with it due to lower W/mk. so will pass thanks

 

[Mr Mcgoo]

New pads may not necessarily fix it if there’s still an issue with the coldplate.

If you do return can recommend the Barrow blocks. Bykski should be decent too. Especially for the price.

will look into thanks