VRM Cooling fans

[malcolmf]

Asus suggest using either a 40 mm or 50 mm fan to provide local cooling, to VRM, on some of their mobos, to aid overclocking. Has anyone tried this, to know if it really makes much difference, and does anyone know a supplier, in the UK, for these. Many thanks.

 

[4745454b]

The "normal" or stock coolers that we've used for so long provide airflow over not just the CPU, but the entire socket area. This does allow for some cooling over the VRMs. Tower coolers like we now use for the better CPU cooling don't give any airflow to the socket area, and the VRMs can and do suffer from the lack of air movement. I was even in a thread maybe 3 or 4 weeks ago where someone had a bad OC and saw a high temp in a program. After helping him track it down, it was the VRMs. He rigged an old 40mm fan to the sinks and got a nearly 20C drop on the VRMs and his OC became stable as well. Does it matter? Very much. You can find dedicated fans I'm sure, but you can also just get an old 40mm fan and just find a way to mount it. Zip ties or if the fins are tight enough, a screw.

 

[william p]

The worst case for VRM airflow is a water loop that removes airflow from the VRM area completely. VRM cooling can provide higher, and more stable Voltage for an overclock. It's very easy to take a step backwards there. It's just as important as CPU cooling.

 

[malcolmf]

The "normal" or stock coolers that we've used for so long provide airflow over not just the CPU, but the entire socket area. This does allow for some cooling over the VRMs. Tower coolers like we now use for the better CPU cooling don't give any airflow to the socket area, and the VRMs can and do suffer from the lack of air movement. I was even in a thread maybe 3 or 4 weeks ago where someone had a bad OC and saw a high temp in a program. After helping him track it down, it was the VRMs. He rigged an old 40mm fan to the sinks and got a nearly 20C drop on the VRMs and his OC became stable as well. Does it matter? Very much. You can find dedicated fans I'm sure, but you can also just get an old 40mm fan and just find a way to mount it. Zip ties or if the fins are tight enough, a screw.

I'm using a 240mm top mounted liquid cooler, so the intake of one of those fans is like 2" from VRM, hence I wondered whether another little fan is going to do much. Plus the suppliers I use, in the UK, don't seem to carry anything smaller than 80mm.

 

[R0GG]

- It makes noticeable difference in temps of my mobo northbrige allowing to maintain temps below 65=T2 (instead of 75 to 80 without VRM fan) system feels staying snappy while gaming.
- There are numerous 60x15mm and 50x15mm 3pin fans, including some blower style small fans on ebay but they have higher RPMs and they are loud (need a low noise adapter with resistor like noctua which have multiple resistors rating up to 100 Ohm) or a molex to multiple 3pin fan adapter with 5V output but very low RPM might not have good cooling efficiency.
- the mounting of the fan could be painful, best solution are old school memory coolers with plastic legs and sometimes mounting clip mono or dual fan but they need at times some work with their connector to make it 3pin and control their RPM (loud)
- There are also some old motherboards Asus small vertical fans (might need some mounting work)
- I used Gskill memory fan on Crosshair formula V north bridge for years in vertical position with metal legs covered with electric type fitting perfectly on VRMs edges modified it into 3 pin fitting mobo and controlled speed through mobo with good results, now using drive cage 2x120mm fans with better results and control over the fans speeds.

 

[vMax]

Interestingly I have a 360 AIO in the top of my case blowing air out of the top and 2 200MM Fans at the front blowing air in. I just bought the H500p Mesh....but the rear 140mm fan I have is blowing air in to the CPU and VRM area...This make a big difference to VRM temps especially as I just have a waterblock from the AIO over the CPU and no active cooling.

So the rear 140mm fan blows air in over the VRM's and then get sucked out the top through the 360 AIO...Overall, I now have great temps across the board...just a thought as it might help.

 

[malcolmf]

- It makes noticeable difference in temps of my mobo northbrige allowing to maintain temps below 65=T2 (instead of 75 to 80 without VRM fan) system feels staying snappy while gaming.
- There are numerous 60x15mm and 50x15mm 3pin fans, including some blower style small fans on ebay but they have higher RPMs and they are loud (need a low noise adapter with resistor like noctua which have multiple resistors rating up to 100 Ohm) or a molex to multiple 3pin fan adapter with 5V output but very low RPM might not have good cooling efficiency.
- the mounting of the fan could be painful, best solution are old school memory coolers with plastic legs and sometimes mounting clip mono or dual fan but they need at times some work with their connector to make it 3pin and control their RPM (loud)
- There are also some old motherboards Asus small vertical fans (might need some mounting work)
- I used Gskill memory fan on Crosshair formula V north bridge for years in vertical position with metal legs covered with electric type fitting perfectly on VRMs edges modified it into 3 pin fitting mobo and controlled speed through mobo with good results, now using drive cage 2x120mm fans with better results and control over the fans speeds.

Have found that Noctua do a 24V 40 mm 4 wire PWM fan. It sounds, however, like you have to change the plug, in order to connect to a mobo fan header. Asus offer a download, to make a mounting bracket with a 3D printer (wish I had one). Vmax's idea of reversing back fan sounds like decent idea: it would probably also be possible to fit a little air scoop, to redirect air flow. Having slight positive air pressure in case never a bad idea, but probably advisable to fit a filter to what would then be air intake.

 

[vMax]

- It makes noticeable difference in temps of my mobo northbrige allowing to maintain temps below 65=T2 (instead of 75 to 80 without VRM fan) system feels staying snappy while gaming.
- There are numerous 60x15mm and 50x15mm 3pin fans, including some blower style small fans on ebay but they have higher RPMs and they are loud (need a low noise adapter with resistor like noctua which have multiple resistors rating up to 100 Ohm) or a molex to multiple 3pin fan adapter with 5V output but very low RPM might not have good cooling efficiency.
- the mounting of the fan could be painful, best solution are old school memory coolers with plastic legs and sometimes mounting clip mono or dual fan but they need at times some work with their connector to make it 3pin and control their RPM (loud)
- There are also some old motherboards Asus small vertical fans (might need some mounting work)
- I used Gskill memory fan on Crosshair formula V north bridge for years in vertical position with metal legs covered with electric type fitting perfectly on VRMs edges modified it into 3 pin fitting mobo and controlled speed through mobo with good results, now using drive cage 2x120mm fans with better results and control over the fans speeds.

Have found that Noctua do a 24V 40 mm 4 wire PWM fan. It sounds, however, like you have to change the plug, in order to connect to a mobo fan header. Asus offer a download, to make a mounting bracket with a 3D printer (wish I had one). Vmax's idea of reversing back fan sounds like decent idea: it would probably also be possible to fit a little air scoop, to redirect air flow. Having slight positive air pressure in case never a bad idea, but probably advisable to fit a filter to what would then be air intake.

Hi malcolmf, yes I do use a filter..cheapo ebay one... Always important! Worth testing out to see what temps you get at load with a 120 or 140mm fan blowing back in from the rear on VRM temps.

 

[vMax]

40mm fans in the UK...Novatech do some here: https://www.novatech.co.uk/products/components/cooling/fans/40-70mm/
Overclocker have a load here: https://www.overclockers.co.uk/air-cooling/fans/by-size/40mm-pc-fans

Hope this helps..

 

[R0GG]

24 is no good for a PC, plenty of 12v fans out there older motherboards smaller chpiset fans especially from asus, sold on ebay, I recently had to upgrade small Form factor PC: digital storm bolt first edition with custom hardware and wanted to improve it's cooling, I got a blower style 60x20 3pin sucking air from outside blowing it on SFF PSU (90 degrees airflow redirection)+ 3x 60x12 mm small fans uptop case cover 1 intake and 2 exhaust above GPU+PSU all 4 fans are 3 pin attached to a molex to 4x3pin 5Volts fan splitter = very quiet operation (with Low-Noise Fan Connector of 50 Ohm fans were still loud)

 

[malcolmf]

- It makes noticeable difference in temps of my mobo northbrige allowing to maintain temps below 65=T2 (instead of 75 to 80 without VRM fan) system feels staying snappy while gaming.
- There are numerous 60x15mm and 50x15mm 3pin fans, including some blower style small fans on ebay but they have higher RPMs and they are loud (need a low noise adapter with resistor like noctua which have multiple resistors rating up to 100 Ohm) or a molex to multiple 3pin fan adapter with 5V output but very low RPM might not have good cooling efficiency.
- the mounting of the fan could be painful, best solution are old school memory coolers with plastic legs and sometimes mounting clip mono or dual fan but they need at times some work with their connector to make it 3pin and control their RPM (loud)
- There are also some old motherboards Asus small vertical fans (might need some mounting work)
- I used Gskill memory fan on Crosshair formula V north bridge for years in vertical position with metal legs covered with electric type fitting perfectly on VRMs edges modified it into 3 pin fitting mobo and controlled speed through mobo with good results, now using drive cage 2x120mm fans with better results and control over the fans speeds.

Have found that Noctua do a 24V 40 mm 4 wire PWM fan. It sounds, however, like you have to change the plug, in order to connect to a mobo fan header. Asus offer a download, to make a mounting bracket with a 3D printer (wish I had one). Vmax's idea of reversing back fan sounds like decent idea: it would probably also be possible to fit a little air scoop, to redirect air flow. Having slight positive air pressure in case never a bad idea, but probably advisable to fit a filter to what would then be air intake.

Hi malcolmf, yes I do use a filter..cheapo ebay one... Always important! Worth testing out to see what temps you get at load with a 120 or 140mm fan blowing back in from the rear on VRM temps.

I did a typo. Noctua fan is 12v. I've got a Phanteks Enthoo case coming tomorrow, so got plenty of general cooling options. Will try it with 140mm rear fan reversed, and see what sort of results I get. Thanks for all help.

 

[william p]

You can light a stick of incense and put it by the VRMs to check for air flow. Fans don't throw air straight out the back. It spreads out in a big shallow cone actually. Silverstone makes some AP "air penatrator " fans that do throw air over distance.