H75 on i7 2600K high temps (even after reseat)

Hello all,

 

I own a H75 for years installed on an i7 2600K. As of lately I tried some mild OC but temps were kinda intimidating. So I took everything apart and blowed dust out of the case (a 600T graphite), also disassembled the H75 cleaned old thermal paste, applied new (MX4) and put all back again and tested once more.

 

I am getting like 40C on CPU package on idle according to HWMonitor which I consider a high value.

 

What I noticed is:

 

1) The backplate is kinda loose (mobo is Asus P8-Z68V Pro).

 

2)The backplate standoffs spin when I try tightening the thumb screws as if they don't hold firm on the backplate. As a result the screws don't secure.

 

The standoffs' pins sockets are of plastic while the standoffs are of metal. As Metal is a lot harder than Plastic I suspect that in my effort to tighten the thumb screws, the standoffs' pins were trimmed, unable to hold the standoffs anymore, and now they spin along with the thumb screws. :(:

 

So my suspicion is the pump unit isn't secured as should, and as a result getting the high temps reported.

 

I don't know if Corsair supplies the backplate on a more durable version (plastic versus metal seems like not a good choice) but I find this on Ebay which is all metal and claims to be compatible with H75.

 

https://www.ebay.com/itm/115x-1366-CPU-Mounting-Hardware-For-CORSAIR-H45-H55-H75-H80I-V2-H100i-V2-H115i/312602466079?hash=item48c88f171f:g:HEEAAOSwEDVc09ay

 

What options do I have? Any opinions or advice will be highly appreciated.

 

Thank you.

The bracket that Corsair includes is the standard Asetek bracket; you'll see it on a number of Asetek OEM coolers. While it is going to be loose against the mainboard, the standoffs aren't supposed to spin. So yeah, I would tend to agree with your assessment - you don't have good contact. You can certainly get a replacement from the Corsair store but it's going to be identical to the one that you have. Or you can give that one a shot - I've no idea if it'll do what it says or not because I've not tried it.

Before chasing down the replacement bracket, you might want to make sure it is contact instead of a cooler issue. Both can cause high idle. The observable difference on the H75 will be a contact issue results in horrific temperatures any time you add load -- instantly. Launch this browser - 65C. Launch a game or stress test -- instant 90C. A problem with the cooler would start off almost normal, but get progressively worse the longer you try. Idle starts at 30C, but soon it's 35 then 40C. The other difference is lingering temperature penalties. With the contact problem, as soon as you drop the Vcore back to idle values, the temp will return to 40C or wherever it is was before. With a cooler issue, you run Intel XTU for 5 minutes and then stop. Now your idle is 55C instead of 40C. It's a little trickier to sort these models without a coolant temp sensor.

Thanks both for your replies.

 

@DevBiker I won't be going back to this plastic backplate, I was about to even ditch it and go for an air cooler. Really disappointed on the quality of this specific part. This is maybe the 3rd time I put out the pump and reapply thermal paste in like 5 years I own it, how can it be that sensitive? There are reports of the issue over the internet so it seems I am not the only one.

In the past I had two H50s no issues at all, even reinstalling them a couple of times. I was looking at replacing it with a 'compatible' backplate made of metal - read that maybe H60 or H80i are compatible with H75, have to research more on that though.

 

@c-attack Right now I am on stock clock. In BIOS I get around 38C, in Windows this goes up on 40C (idle). Launching a game gets me around 60C. I don't have extreme temp jumps like you describe (thank god). But when I started investigating the first time I removed the pump I saw the old paste being pushed to the edge of the IHS and in the IHS center remnants of paste in a manner air was flowing in between - that put me into suspicion regarding the secure mounting of the pump on the backplate, etc. I can't do more than what I 've already done, spent many hours on this and there is no solution since the screws never tighten but spin endlessly.

 

For your better understanding this is what I encountered.

https://forums.hardwarezone.com.sg/convergent-ecustomer-service-center-184/corsair-h75-backplate-issue-4502145.html