High load temps on new W/C Loop

[Kangaxx]

I recently partook in a new watercooling loop after many years away from watercooling. I picked up a v8 bundle from OcUK here, with the HL black ice rad, and some Mayhems pastel fluid.

Now, its been many years since I did my last loop (I was cooling a socket A AMD chip, so yes, its been a while!) so I am not totally foreign to the principles and how-to on settings up a loop, but this problem is really bizarre.

The loop is installed, with flow going...

Pump/Res -> CPU -> Rad -> pump/res

nothing too exotic there. I did the usual leak testing, but this is where things have changed a bit. In the dim and distant past, I assembled my loop outside of the chassis, and ran it off the PSU for x hours for leak testing. The advantage of this being that you could really shift the Rad and blocks about to get all the air out. Problem is, with this new kit, that ain't possible, so I followed the instructions and installed, primed and bled it in the chassis. Did I get all the air out? I think I did, but its hard to say.

Anyway, onto the problem. It's all running now, great. Idle temps are slightly lower than they were with my K2 Mount DOOOOM (about 30 degrees now), but the load temperatures are off the scale. I have seen 3 of my cores hit 105 degrees, which I believe is the max temp for this CPU (which incidentally is an Intel i5-3570k running at 4.4 ghz on 1.32v). I should add that for reasons I have never understood, core 1 always sits about 20 degrees cooler than the others. Did on the air cooler and does on the water block. I will also add that on air, the temp would only get to 80-90 degrees on heavy load (prime).

So, what have I done to try and sole this puzzle? Well, here you go...

1). Re-seated the CPU block.
2). Checked (best I can) for air in the Rad. Don't think there is any in there.
3). Lowered the OC on the CPU to 4 ghz, but the temps are still shooting up to the max as soon as the CPU is stressed.
4). Checked the loop for any kinks etc. and there are none.

Now, to my knowledge, it would seem that the pressure/flow through the block isn't high enough, as the coolant isn't shifting the temperature away from the block fast enough. However, this is a simple loop with a reasonable pump/res combo (XSPC 750), so I can't see how it would be that. I have got the flow going the correct way through the block before you ask.

Too much thermal paste maybe? I did clean off the old stuff (AS5 i believe it was) and used the XSPC paste instead. Could too much of that cause this issue?

So, I put it to you, can anyone think of any reason why the loop would be doing this?

Thanks in advance!

 

[BluSky]

Air wouldn't affect temps that much... I would ask if the pump is working properly but your idle temps indicate it probably is.

Did you peel the clear film off the bottom of the CPU block? I had your symptoms once and had forgotten to do that.

Failing that the only thing I can think of is terrible contact between the CPU cooler and block. Assuming you haven't absolutely caked it in thermal paste, is it definitely screwed down tight? What did the paste look like when you removed the block - were there clear signs of contact?

Lastly it would be useful to know what CPU you are running and how many volts you are putting through it... just to have a more accurate idea of the temps we should be expecting.

 

[Ploppy2k3]

usually this is air in the rad. have you really tilted you case over 70 degrees or more? my front rad needs a big tilt to get all the air out.

can you feel the vibration of the pump?

 

[Ploppy2k3]

you will be amazed as well how far you can screw the raystorm down! and need to in order to get good temps. I have the 2nd stage screws all the way down.

 

[tamzzy]

if your cores are hitting tjmax, then there's definitely something major wrong. my 1st guess would be pump (assuming you fitted the block correctly)

 

[Kangaxx]

Did you peel the clear film off the bottom of the CPU block? I had your symptoms once and had forgotten to do that.

Checked, i definitely removed it.

Failing that the only thing I can think of is terrible contact between the CPU cooler and block. Assuming you haven't absolutely caked it in thermal paste, is it definitely screwed down tight? What did the paste look like when you removed the block - were there clear signs of contact?

Yes, all 4 top screws are tightened up as far as they will go, and the lower nuts are pretty much as tight as they will go as well. I must admit, I am a bit paranoid to tighten it much more. Don't really wanna crush the CPU. The thermal paste had spread out, and was covering the entire heat spreader. I wouldn't say it was caked, i did put more on the normal (more accident than anything), but we are talking maybe 3 grains of rice worth?

Lastly it would be useful to know what CPU you are running and how many volts you are putting through it... just to have a more accurate idea of the temps we should be expecting.

I did put it in my post, guess you missed it, so here is it again..

Intel i5-3570k running at 4.4 ghz on 1.32v

if your cores are hitting tjmax, then there's definitely something major wrong. my 1st guess would be pump (assuming you fitted the block correctly)

The pump is definitely on. Faulty? How can I say or tell? The damn thing is near silent, and went hell for leather when i was priming the system, so AFAIK, its working fine.

usually this is air in the rad. have you really tilted you case over 70 degrees or more? my front rad needs a big tilt to get all the air out.

Yep, tilted it a good 60 degrees in all directions (apart from turning the whole chassis upside down, but as its a corsair 750D, it is rather heavy )

I think I will re-seat the block again, check the rear mounting plate and re-apply the thermal paste. And maybe try inverting the case completely, just to ensure the air is all out

Thanks for your help and suggestions so far guys. if anyone has any other bright ideas, please share

 

[BluSky]

Checked, i definitely removed it.

I did put it in my post, guess you missed it, so here is it again..

Intel i5-3570k running at 4.4 ghz on 1.32v

So you did, apologies for missing that.

3 grains of rice sounds like a bit too much, but something else is amiss here I think. It sounds like mounting pressure / contact is probably OK if the paste has spread out well.

I take it 1.32v is what you have set in the bios. What does something like cpu-z report as the actual voltage at load? Do you have LLC turned up?

You already said you checked the flow direction is set up properly... I am running out of ideas here.

How much fluid did it drink when you filled it up?

Could you post a picture of it? You never know, we might be able to spot something.

 

[ubersonic]

Is the rad getting hot? how about the air coming off the rad that feel hot? and the tubing?

What type of motherboard you got? could be the board is running the fans at reduced speed.

 

[stuie]

The pump is definitely on. Faulty? How can I say or tell? The damn thing is near silent, and went hell for leather when i was priming the system, so AFAIK, its working fine.

Sorry can you explain that last bit as it sounds like your suggesting the pump spools up with load. You have got your pump plugged into a 4 pin molex connecter havnt you?

 

[NoobCannon]

Hes saying he heard it when he was filling the loop And now cant hear it. Possible killed the pump when filling/priming

To the op, feel the pump with the system on if its not vibrating/humming then id say its dead so start checking power etc.

 

[pastymuncher]

Have you got the Inlets/Outlets connected the right way around on the pump/res and block?

***Edit*** Sorry missed the bit where you said you checked that.

 

[Kangaxx]

Once again, thank you for all your replies.

I took the PC apart again, checked the mounting of the block. It was pretty tight, but the bottom screws could have gone tighter. In any case, I removed the block, removed the paste from the block and gave the CPU a good clean. I remounted it using Arctic Cooling MX-2, this time with only 1 grain of rice worth, checked the backing plate (which was fine) and remounted the block. I tightened the top bolts evenly and as tight as they will go, and then did the same for the lower knurls. They are now as tight as I can make them, without using a wrench (shredded my fingers in the process!)

Ran the pump on its own (yes, it does still turn on) I can hear it humming, and if that isn't enough, I totally inverted the chassis, to ensure there was no air still in the rad, and I could hear the pump working. Left it for a lil' while to ensure of no new leaks, and have now got it all hooked back up.

Has it made any difference? Not really. I still have the strange situation where core 0 is 20 degrees cooler than the other 3, but under intense load (using Intel Burn test), the temperatures are still skyrocketing to 100+ degrees.

Now Tj max for this CPU is 105 degrees, but when it hits that, the PC doesn't shut down or panic, which is what I thought would happen. Also, and this may just be me not knowing any better, but the temps vary VERY quickly. In the past, CPU core temps would increase over a period of time, if the CPU was under load. As soon as I start the stress test, and the load hits 100% at full tilt (4.4ghz) the temp immediately goes up. Is that correct? Is it possible there is a sensor awry somewhere?

In answer to the other questions, the radiator doesn't appear to be "hot", its warm, certainly, which is what I would expect it to be. The Fans are set to auto in the BIOS, and have been volt'd down with the resistors that came with the Corsair fans. They are definitely both working, and pushing a fair bit of air through the Rad. I used nearly the entire litre of Mayhems fluid. I think there is a tiny bit left in the bottle (which I could probably squeeze in if I wanted).

I will take some pictures if you really think it will help, and post the outputs I get from CPU temp as well in a bit.

Thats all I can think of at the moment. I appreciate all the suggestions so far

 

[Kangaxx]

Here is the picture of the temperatures from the last test I performed. You can see the jump from low temps to high temps as well with that picture.

 

[stuie]

could you post some pics of your loop? something not rigt there

 

[tamzzy]

just a quick thought. on the cpu block, did you connect the inlet and outlet properly? if water is going the wrong way, that could explain the temps i guess

 

[SouthEastBlue]

I know this may be a pain, but have you tried this CPU on the stock cooler, or another fan/heatsink cooler to see if you have some weird temp readings or a faulty CPU?

If you're idling at 30 celcius surely that is pretty normal? But your peak temps, and weird 30 celcius lower on one core is pretty strange.

 

[Kangaxx]

could you post some pics of your loop? something not rigt there

I will post some tonight, although I have more information which may render this unnecessary.

just a quick thought. on the cpu block, did you connect the inlet and outlet properly? if water is going the wrong way, that could explain the temps i guess

I have checked this, the water is def. flowing the right way

I know this may be a pain, but have you tried this CPU on the stock cooler, or another fan/heatsink cooler to see if you have some weird temp readings or a faulty CPU?

Yes, this would be a pain, but I know where you are coming from. I did have this on air before moving to the loop, and the core temp strangeness occurred with that too. All I can assume is that core 0 has a good contact with the heat spreader and the other 3 don't. However, I don't want to risk de-lidding it (not with my ham fisted approach to things anyway).

Anyway, I have been fiddling, and have done the following..

1). Flashed the BIOS to the latest, Beta version from gigabyte (the motherboard is a G1.Sniper M3, in case you are interested)
2). Altered the overclock slightly. Previously, the core was set to 1.3v. I have now lowered this to 1.25v

Since I have done the above, the peak temperatures have dropped. When running the stress test this morning, the hottest core (core 2) peaked at 96 degrees. Hot, yes, but not too hot. I have also noticed that under a "normal" 100% load (I use BOINC, so this is what I have been using to apply a "normal" 100% load), the temperatures now don't go above 80 degrees.

The idle temps do seem lower, even though nothing physical was changed after I did the above, so can only assume the new BIOS has improved the temperature sensing on the mobo, and the reduction in voltage will obviously help with this as well (unsure why it was set to 1.3v. System seems happy and stable at 1.25v with the multi at 44x)

Here is a pic of a test just performed with the stress test running..

I think I will monitor it for now. I rarely put the CPU under massive stress, so I am happy that the temps are not going to be a problem now.

Many many thanks for all the suggestions etc.

 

[stuie]

Something still doesnt seem right over 90c under water at just 1.25v seems wrong. My 3770k also under water also at 1.25v 4.5ghz never goes above 80 normally in high 70s with IBT and I've got 2 670s in the loop too

 

[Kangaxx]

Something still doesnt seem right over 90c under water at just 1.25v seems wrong. My 3770k also under water also at 1.25v 4.5ghz never goes above 80 normally in high 70s with IBT and I've got 2 670s in the loop too

Fair enough, but I think your loop has considerably more cooling power, if your sig is up to date, even with the additional graphics cards

I will post some pictures of the rig later on when I have a chance.

 

[ubersonic]

Have you tried removing the overclock and seeing what happens? under normal clocks if the problem is with the loop it should have the same effect just take longer to get there.