Cooling Asetek 645LT and more (FAQ / AMA)

AseDen

Cable-Tie Ninja
Original poster
Asetek
Dec 7, 2018
194
295
www.asetek.com
Hello wonderful SmallFormFactor Forum!

I tend to get quite a few questions from wonderful users of the Asetek 645LT, and I wanted to create a go-to place for the most common questions, as well as somewhere everyone can feel welcome to ask any question that relates to the 645LT, Asetek or even me as an Asetek employee/face of the company, in the community.

Now that we have the name and purpose of the thread explained, I'd like to take a few sentences to tell you about a specific question that got me to make this thread.
Again and again, I've been asked how much liquid is in the 645LT and whether or not it's 'safe' to bring it on an airplane. I thought about it, and figured: "what an obvious question for a SFF cooler".

So here we are!

This thread will be updated as is necessary, and I will try to keep it looking somewhat clean.

Please remember that there are no such thing as stupid questions, only stupid answer (Just made myself feel the pressure! ;))

AMA/FAQ:

645LT Specific

  • How much liquid is in the 645LT?
    • There is approximately 65ml of liquid in the 645LT. So don't worry about TSA regulations of 100ml.
  • What are the dimensions and specifications of the 645LT?
    • Radiator measurements are: 118 x 97 x 35mm
    • Pump / Block combo: 29.8mm tall
    • Pump RPM: 2800 RPM (don't worry about read-outs saying 5600RPM - it's a read out error on motherboards)
    • Minimum start voltage: 8V
    • Rated power: 2.16W
    • Tube length: 250mm
    • Supported fan size: 92mm (up to 15mm thick on the primary side - ie. under angled bends) and any on the opposite side.
    • Technology: Asetek Generation 6
    • Official CPU socket support: LGA 115x, 1366, 2011, 2011-3, 2066, AM4 (it will also work on other platforms with correct retention, however they are not officially supported)
    • Max. operating liquid temperature: 60C
    • Total weight: 465g

Asetek Specific
  • Is it safe to bring an Asetek liquid cooler on a plane (will it cause leaks due to pressure differences?)
    • Yes! It is absolutely safe and it won't cause a leak. The more elaborate answer is: At the surface of the earth pressure is roughly 1bar. When you're in a plane, you're obviously way above the surface of the earth, but even if you were to head to outer space (absolute vacuum) the pressure would only be reduced to 0bar. This brings the pressure difference to a total of 1bar (the parameter that determines whether or not a leak would be plausible/imminent) between the inside and the outside of the loop. All Asetek products adhere to strict certifications, one of which is UL certification. Under the approval process of getting UL certification, you (we as a company) have to prove that our products can withstand pressure tests at 3.6bar (some components as much as 9bar).
      Funny side note: We regularly ship entire pallets with air freight. Nothing to worry about :)
  • Where should I connect my AIO?
    • Ideally you'll want to connect your Asetek AIO (pump connector) to the CPU_FAN port of your motherboard. This is to ensure that the pump is always running, and you'll maintain the warning features of the CPU_FAN port. Also, you won't get wrong read outs about pump speed.
Asetek Dennis

Please feel free to ask any questions or comments in the thread :)

/Asetek Dennis

Updated: 21-11-2019
 
Last edited:

zedstar

Chassis Packer
Jun 7, 2017
19
1
here are my questions, I just bought the pump but not having much success with cooler temps. (Ryzen 3600x on Asrock Fatal1ty mobo in a DAN SFX case).

When i bought i there was no instruction manual, so i didnt know i had to use the original backplate (was really scratching my head on that one for a while).

1. what should we see as the operating temperature on idle and at full ?
2. in a dan SFX A4 case should we do push or pull on the fan on top of pump?
3. I have heard that running the pump at >60c continuously has potential negative consequences.
4. what other tuning recommendations are there to run cool? i am nowhere near any of the published temps for this setup.
 

Baesamic Vinegar

Case Bender
New User
May 9, 2020
2
1
Hey Dan,

I bought an asetek 645LT in march and it was working fine until now. Whenever I boot up my computer after leaving it off for a while (after going to bed) the pump stops working until I restart or manually change the pump mode from DC to PWM then back to DC. However, when I restart my computer after applying theses changes the pump starts working fine again and has no issues and boots up perfectly fine. Has anybody had this issue before? if so how did you guys fix it?

Thanks!
 

AseDen

Cable-Tie Ninja
Original poster
Asetek
Dec 7, 2018
194
295
www.asetek.com
here are my questions, I just bought the pump but not having much success with cooler temps. (Ryzen 3600x on Asrock Fatal1ty mobo in a DAN SFX case).

When i bought i there was no instruction manual, so i didnt know i had to use the original backplate (was really scratching my head on that one for a while).

1. what should we see as the operating temperature on idle and at full ?
2. in a dan SFX A4 case should we do push or pull on the fan on top of pump?
3. I have heard that running the pump at >60c continuously has potential negative consequences.
4. what other tuning recommendations are there to run cool? i am nowhere near any of the published temps for this setup.

1. That depends entirely on your setup :)
2. I suggest doing pull, to get the coolest possible air for the AIO
3. Depends. CPU temp can be more than 60C no problem. Liquid temp at more than 60C is bad :)
4. A couple of things I know tend to work:
a) Custom cables (kit available I think.)
b) Raising the PSU (there's a guy on reddit, should find him if you search for DAN A4 kit, I would think)
c) Undervolt the CPU

I hope this helps :)
Otherwise feel free to follow up :)


Hey Dan,

I bought an asetek 645LT in march and it was working fine until now. Whenever I boot up my computer after leaving it off for a while (after going to bed) the pump stops working until I restart or manually change the pump mode from DC to PWM then back to DC. However, when I restart my computer after applying theses changes the pump starts working fine again and has no issues and boots up perfectly fine. Has anybody had this issue before? if so how did you guys fix it?

Thanks!

That sounds very odd!!! Never heard of anything along these lines.
Is it running on AIO_PUMP or CPU_FAN? (Latter is better).

//Asetek Dennis
 

Baesamic Vinegar

Case Bender
New User
May 9, 2020
2
1
My MSI b450 itx has CPU_FAN and SYS_FAN ports so I plugged the pump into the SYS_FAN port and then switched it over to CPU_FAN to see if it fixed the issue and it didn't so i switched it back. It just seems extremely strange because the pump works completely fine during normal day to day uses but doesn't seem to want to start on bootup after being turn off for a while. This seems more like a software issue rather than with the hardware so im not sure.
 
  • Like
Reactions: AseDen

AseDen

Cable-Tie Ninja
Original poster
Asetek
Dec 7, 2018
194
295
www.asetek.com
It does sound like some software issue. But there’s no software for the 645LT so it would have to be on the motherboard end, if it’s non internal hardware :-/
 

beastmonkey

Chassis Packer
Jan 23, 2020
19
6
does it make a difference in the dan a4 if the fan is mounted on the bottom or top of the radiator (assuming both positions with the fan on intake pull).
 
  • Like
Reactions: AseDen

GNW20000

What's an ITX?
New User
May 14, 2020
1
1
Hi Dan, not sure if this is the right place for my question, but I saw that the storefront on SFFLAB.com (W360MOD.com) went live just recently, however 645lt seemed to be sold out already. Do you have any information on the production schedule (release interval and batch size etc.)? Thanks!
 
  • Like
Reactions: AseDen

AseDen

Cable-Tie Ninja
Original poster
Asetek
Dec 7, 2018
194
295
www.asetek.com
does it make a difference in the dan a4 if the fan is mounted on the bottom or top of the radiator (assuming both positions with the fan on intake pull).

It really depends on the rest of your system. If you want the best possible acoustics and performance you'll want to run custom length cables and potentially use the kit you can find on reddit (which moves your PSU slightly higher in the case).
Additionally you flip the aio 180 degrees (tubes in the bottom on the case, then fan, then rad, then PSU - that will give you the best acoustic (and potentially thermal) performance. This has to do with the way air moves in the system :)

Hi Dan, not sure if this is the right place for my question, but I saw that the storefront on SFFLAB.com (W360MOD.com) went live just recently, however 645lt seemed to be sold out already. Do you have any information on the production schedule (release interval and batch size etc.)? Thanks!

Hi GNW,

I have not heard anything to that end. But I will reach out to our responsible sales director and inquire about the status.
It should also be available at Overclockers.co.uk, Sliger cases and Caseking.de.

Best,
AsetekDennis
 
  • Like
Reactions: Phuncz

AseDen

Cable-Tie Ninja
Original poster
Asetek
Dec 7, 2018
194
295
www.asetek.com
@AseDen

Hi Dan, what do you think about this video, do you think that this is really such a big issue?


Sorry for being lazy and not realizing this post was here. My bad! Thought I had enabled email notifications ?

I'm one of his sources for information on why AIO orientation matters.
That being said, I think that there's a level of "drama" added to the content piece (and obviously the title) - but it's probably needed to drive clicks. That being said, there are of course merits to the claims made. Having the "wrong" orientation won't kill your AIO for any forseeable future unless it was constructed horribly and/or without sense of Quality & Control.
You are however likely to experience "gurgling" as I'm sure most SFF builders are aware of. It's not damaging (in any real or measurable way) unless you get to a point where evaporation through the tubes has allowed the pump to run completely dry (or maybe use a manufacturer that leaves 10% air in there - nearly choked on my coffee, there ?).

I would assume this mostly relates to the 645LT.
As I've mentioned on here a few times, it's fine to run it in its natural position in the Dan-Cases A4-SFX. Absolutely fine! You may experience the pump gurgling - because it's vertically above the radiator/hex. Now, there's a relatively easy (as if anything is easy in SFF, lol!) fix, which is flipping the rad 180 degrees, having tubes at the bottom of the case. This will allow air bubbles to stick in the rad/hex rather than the pump/block combo.

As always, happy to discuss further and/or get more in-depth :)
 
  • Like
Reactions: tinyitx

aleck

Caliper Novice
Dec 8, 2019
30
10
Many thanks for being here.

Additionally you flip the aio 180 degrees (tubes in the bottom on the case, then fan, then rad, then PSU - that will give you the best acoustic (and potentially thermal) performance. This has to do with the way air moves in the system :)

Because the radiantor will then be very close to PSU, would it be better to orient the fans to exhaust the air out (since intake air would hit the PSU and go nowhere)?
 

riba2233

Shrink Ray Wielder
SFF Time
Jan 2, 2019
1,720
2,242
www.sfftime.com
Sorry for being lazy and not realizing this post was here. My bad! Thought I had enabled email notifications ?

I'm one of his sources for information on why AIO orientation matters.
That being said, I think that there's a level of "drama" added to the content piece (and obviously the title) - but it's probably needed to drive clicks. That being said, there are of course merits to the claims made. Having the "wrong" orientation won't kill your AIO for any forseeable future unless it was constructed horribly and/or without sense of Quality & Control.
You are however likely to experience "gurgling" as I'm sure most SFF builders are aware of. It's not damaging (in any real or measurable way) unless you get to a point where evaporation through the tubes has allowed the pump to run completely dry (or maybe use a manufacturer that leaves 10% air in there - nearly choked on my coffee, there ?).

I would assume this mostly relates to the 645LT.
As I've mentioned on here a few times, it's fine to run it in its natural position in the Dan-Cases A4-SFX. Absolutely fine! You may experience the pump gurgling - because it's vertically above the radiator/hex. Now, there's a relatively easy (as if anything is easy in SFF, lol!) fix, which is flipping the rad 180 degrees, having tubes at the bottom of the case. This will allow air bubbles to stick in the rad/hex rather than the pump/block combo.

As always, happy to discuss further and/or get more in-depth :)


Don't worry, I really appreciate the reply!

I just wanted a confirmation from first hand that nothing bad will happen (except for potentially a bit more noise) if the pump is in the highest point of the loop, as this is the only way in my P-ATX case. So that I can recommend Asetek units to my customers, because as you've said, others can leave too much air in it.

BTW I personally use Asetek AIO in my P-ATX (Asus ryuo 120) and it performs really nice, temperatures are very good and I can only barely hear the pump at max rpm only if other fans are at really low rpm. But it automatically lowers rpm at idle so I don't hear it at all.
 
Last edited:

AseDen

Cable-Tie Ninja
Original poster
Asetek
Dec 7, 2018
194
295
www.asetek.com
Don't worry, I really appreciate the reply!

I just wanted a confirmation from first had that nothing bad will happen (except for potentially a bit more noise) if the pump is in the highest point of the loop, as this is the only way in my P-ATX case. So that I can recommend Asetek units to my customers, because as you've said, others can leave too much air in it.

BTW I personally use Asetek AIO in my P-ATX (Asus ryuo 120) and it performs really nice, temperatures are very good and I can only barely hear the pump at max rpm only if other fans are at really low rpm. But it automatically lowers rpm at idle so I don't hear it at all.

Absolutely my pleasure to help out!
Wonderful to hear that you're loving the Ryuo 120. Really like the look of the Ryuo units myself - actually wanted to do a themed build with the Strix White :-D

Many thanks for being here.



Because the radiantor will then be very close to PSU, would it be better to orient the fans to exhaust the air out (since intake air would hit the PSU and go nowhere)?

Some thoughts here would be:
  1. In the usual config with pull, the air would still hit the PSU (as the cumulative height is the same)
  2. Inversed should (without having in-depth knowledge on it) be the same as #1
  3. Pulling through will leave you with some amount of pre-heat from the case leading to, potentially, higher temps.
Now all of these would need some testing to verify. But I suspect that either way, there will be minor differences in temps - but it's hard to comment specifically on without testing it out :)
 
  • Like
Reactions: riba2233

SFF Watercooled

Master of Cramming
Sep 26, 2020
399
172
Hello wonderful SmallFormFactor Forum!

I tend to get quite a few questions from wonderful users of the Asetek 645LT, and I wanted to create a go-to place for the most common questions, as well as somewhere everyone can feel welcome to ask any question that relates to the 645LT, Asetek or even me as an Asetek employee/face of the company, in the community.

Now that we have the name and purpose of the thread explained, I'd like to take a few sentences to tell you about a specific question that got me to make this thread.
Again and again, I've been asked how much liquid is in the 645LT and whether or not it's 'safe' to bring it on an airplane. I thought about it, and figured: "what an obvious question for a SFF cooler".

So here we are!

This thread will be updated as is necessary, and I will try to keep it looking somewhat clean.

Please remember that there are no such thing as stupid questions, only stupid answer (Just made myself feel the pressure! ;))

AMA/FAQ:

645LT Specific

  • How much liquid is in the 645LT?
    • There is approximately 65ml of liquid in the 645LT. So don't worry about TSA regulations of 100ml.
  • What are the dimensions and specifications of the 645LT?
    • Radiator measurements are: 118 x 97 x 35mm
    • Pump / Block combo: 29.8mm tall
    • Pump RPM: 2800 RPM (don't worry about read-outs saying 5600RPM - it's a read out error on motherboards)
    • Minimum start voltage: 8V
    • Rated power: 2.16W
    • Tube length: 250mm
    • Supported fan size: 92mm (up to 15mm thick on the primary side - ie. under angled bends) and any on the opposite side.
    • Technology: Asetek Generation 6
    • Official CPU socket support: LGA 115x, 1366, 2011, 2011-3, 2066, AM4 (it will also work on other platforms with correct retention, however they are not officially supported)
    • Max. operating liquid temperature: 60C
    • Total weight: 465g

Asetek Specific
  • Is it safe to bring an Asetek liquid cooler on a plane (will it cause leaks due to pressure differences?)
    • Yes! It is absolutely safe and it won't cause a leak. The more elaborate answer is: At the surface of the earth pressure is roughly 1bar. When you're in a plane, you're obviously way above the surface of the earth, but even if you were to head to outer space (absolute vacuum) the pressure would only be reduced to 0bar. This brings the pressure difference to a total of 1bar (the parameter that determines whether or not a leak would be plausible/imminent) between the inside and the outside of the loop. All Asetek products adhere to strict certifications, one of which is UL certification. Under the approval process of getting UL certification, you (we as a company) have to prove that our products can withstand pressure tests at 3.6bar (some components as much as 9bar).
      Funny side note: We regularly ship entire pallets with air freight. Nothing to worry about :)
  • Where should I connect my AIO?
    • Ideally you'll want to connect your Asetek AIO (pump connector) to the CPU_FAN port of your motherboard. This is to ensure that the pump is always running, and you'll maintain the warning features of the CPU_FAN port. Also, you won't get wrong read outs about pump speed.
Asetek Dennis

Please feel free to ask any questions or comments in the thread :)

/Asetek Dennis

Updated: 21-11-2019
What if there's a hurricane
 

AseDen

Cable-Tie Ninja
Original poster
Asetek
Dec 7, 2018
194
295
www.asetek.com
Hi Dan,

Is there any optimal curve or rpm for the Asetek pump? Mine's typically chugging between 5000 - 5600.

Actually it's Dennis, but no worries ;-P

So what you're seeing is a wrong readout on your motherboard (has to do with the way RPM are read, which can differ).
So your pump is actually running 2500 - 2800 RPM. 2800RPM is, coincidentally also the rated speed. ;)
If you want to reduce it the best way, out of the box, is by adjusting voltage in your motherboards BIOS.

What if there's a hurricane

Then I'm pretty sure the 645LT will rock you ?
 
  • Like
Reactions: greentypewriter

gpaint45

Caliper Novice
Mar 1, 2020
28
10
Hello wonderful SmallFormFactor Forum!

I tend to get quite a few questions from wonderful users of the Asetek 645LT, and I wanted to create a go-to place for the most common questions, as well as somewhere everyone can feel welcome to ask any question that relates to the 645LT, Asetek or even me as an Asetek employee/face of the company, in the community.

Now that we have the name and purpose of the thread explained, I'd like to take a few sentences to tell you about a specific question that got me to make this thread.
Again and again, I've been asked how much liquid is in the 645LT and whether or not it's 'safe' to bring it on an airplane. I thought about it, and figured: "what an obvious question for a SFF cooler".

So here we are!

This thread will be updated as is necessary, and I will try to keep it looking somewhat clean.

Please remember that there are no such thing as stupid questions, only stupid answer (Just made myself feel the pressure! ;))

AMA/FAQ:

645LT Specific

  • How much liquid is in the 645LT?
    • There is approximately 65ml of liquid in the 645LT. So don't worry about TSA regulations of 100ml.
  • What are the dimensions and specifications of the 645LT?
    • Radiator measurements are: 118 x 97 x 35mm
    • Pump / Block combo: 29.8mm tall
    • Pump RPM: 2800 RPM (don't worry about read-outs saying 5600RPM - it's a read out error on motherboards)
    • Minimum start voltage: 8V
    • Rated power: 2.16W
    • Tube length: 250mm
    • Supported fan size: 92mm (up to 15mm thick on the primary side - ie. under angled bends) and any on the opposite side.
    • Technology: Asetek Generation 6
    • Official CPU socket support: LGA 115x, 1366, 2011, 2011-3, 2066, AM4 (it will also work on other platforms with correct retention, however they are not officially supported)
    • Max. operating liquid temperature: 60C
    • Total weight: 465g

Asetek Specific
  • Is it safe to bring an Asetek liquid cooler on a plane (will it cause leaks due to pressure differences?)
    • Yes! It is absolutely safe and it won't cause a leak. The more elaborate answer is: At the surface of the earth pressure is roughly 1bar. When you're in a plane, you're obviously way above the surface of the earth, but even if you were to head to outer space (absolute vacuum) the pressure would only be reduced to 0bar. This brings the pressure difference to a total of 1bar (the parameter that determines whether or not a leak would be plausible/imminent) between the inside and the outside of the loop. All Asetek products adhere to strict certifications, one of which is UL certification. Under the approval process of getting UL certification, you (we as a company) have to prove that our products can withstand pressure tests at 3.6bar (some components as much as 9bar).
      Funny side note: We regularly ship entire pallets with air freight. Nothing to worry about :)
  • Where should I connect my AIO?
    • Ideally you'll want to connect your Asetek AIO (pump connector) to the CPU_FAN port of your motherboard. This is to ensure that the pump is always running, and you'll maintain the warning features of the CPU_FAN port. Also, you won't get wrong read outs about pump speed.
Asetek Dennis

Please feel free to ask any questions or comments in the thread :)

/Asetek Dennis

Updated: 21-11-2019
Hello there! In January this year, I built a tiny SGPC K39 case build with a Ryzen 9 3950X w/Gigabyte Aorus X570i Pro Wifi, Alpenfohn Black Ridge w/Noctua NF-A9x14 slim fan, Gigabyte Aorus RTX2070 Mini, 32GB Corsair Vengeance 3200MHz CL16 LPX DDR4 memory. Been running this setup in ECO MODE (65watts). I do light simracing with F1 2018, MotoGP 20, rFactor 2 and Assetto Corsa, as well as the odd capture & rendering of video via Cyberlink PowerDirector 18. Discovered this case currently in Production, which I've put a deposit on when it's ready for shipment.

Wanted your honest opinion on whether your Asetek 645LT would be a better alternative in cooling my 3950X in this new case, seeing that they've tested a Corsair H60 120mm AIO in it; albeit a Ryzen 1700 oc'd to 3800MHz. I'm not an afficionado with watercooling but I know that usually larger radiators mean better cooling. I plan to change my motherboard settings to PBO on Auto, and possibly undervolt to -0.0750mv to help lower temps. Ultimately, I want my new build to be as quiet as possible.
 

AseDen

Cable-Tie Ninja
Original poster
Asetek
Dec 7, 2018
194
295
www.asetek.com
Hello there! In January this year, I built a tiny SGPC K39 case build with a Ryzen 9 3950X w/Gigabyte Aorus X570i Pro Wifi, Alpenfohn Black Ridge w/Noctua NF-A9x14 slim fan, Gigabyte Aorus RTX2070 Mini, 32GB Corsair Vengeance 3200MHz CL16 LPX DDR4 memory. Been running this setup in ECO MODE (65watts). I do light simracing with F1 2018, MotoGP 20, rFactor 2 and Assetto Corsa, as well as the odd capture & rendering of video via Cyberlink PowerDirector 18. Discovered this case currently in Production, which I've put a deposit on when it's ready for shipment.

Wanted your honest opinion on whether your Asetek 645LT would be a better alternative in cooling my 3950X in this new case, seeing that they've tested a Corsair H60 120mm AIO in it; albeit a Ryzen 1700 oc'd to 3800MHz. I'm not an afficionado with watercooling but I know that usually larger radiators mean better cooling. I plan to change my motherboard settings to PBO on Auto, and possibly undervolt to -0.0750mv to help lower temps. Ultimately, I want my new build to be as quiet as possible.

Hi there Gpaint!

Honest opinions.. That's my thing! ;)
So there is a direct correlation between size of the rad and performance.
Furthermore a larger 120mm fan will quite often be able to move more air than a 92mm.

Now, I've heard of people using the 645LT in a system like yours, with decent results. Especially if you can manage to cram something like a Noctua NF-A9x25 onto the radiator. If you are in it for optimal performance both thermally and acoustically, I'd suggest getting a 120mm with a 25mm thick fan on it.

I hope this provides some clarification - otherwise I'm always happy to help :)