Overclock.net › Forums › Cooling › Air Cooling › What part of a VRM should I cool?
New Posts  All Forums:Forum Nav:

What part of a VRM should I cool?

post #1 of 14
Thread Starter 
I see this as a common VRM setup on GPU and MBs, wonder if I should cool the capacitor and chokes in addition to the mosfet/VRM?

From what I've read a "choke" is only a metal block with copper coil inside, no electronics, can survive crazy high temps and doesn't affect operation of the card in the long run. Is this true?

How about capacitors? Should I worry about that too?


If the two components really don't need a heatsink, do we get any benefit in any way when it is cooled? Or is it unnecessary overkill?









Thanks in advance.
紅魔館
(12 items)
 
秋山 澪
(10 items)
 
For Sale: Crucial 2x8GB DDR4 2400 / 1TB 2.5" HDD
$40 (USD) or best offer
CPUMotherboardGraphicsRAM
i7 5820K ASUS X99 Deluxe Zotac GTX 1080 AMP! Crucial Ballistix Sport 4x4G DDR4-2400 
Hard DriveHard DriveOptical DriveCooling
WD Black 4TB Samsung 850 EVO 1TB Dell CH30N BD-Read Noctua NH-D15 
CoolingOSPowerCase
Noctua NF-A14 PWM x6 Windows 10 Enterprise EVGA 750W G2 Phanteks Enthoo Luxe 
CPUMotherboardGraphicsGraphics
i7 7700K P870KM1 Nvidia GeForce GTX 1080 Nvidia GeForce GTX 1080 
RAMHard DriveOSMonitor
16GB DDR4 2133 Samsung 850 EVO 500GB Windows 10 Enterprise AUO B173QTN01.0 2560x1440p G-sync  
PowerCase
Eurocom 780W Clevo P870KM1 
  hide details  
Reply
紅魔館
(12 items)
 
秋山 澪
(10 items)
 
For Sale: Crucial 2x8GB DDR4 2400 / 1TB 2.5" HDD
$40 (USD) or best offer
CPUMotherboardGraphicsRAM
i7 5820K ASUS X99 Deluxe Zotac GTX 1080 AMP! Crucial Ballistix Sport 4x4G DDR4-2400 
Hard DriveHard DriveOptical DriveCooling
WD Black 4TB Samsung 850 EVO 1TB Dell CH30N BD-Read Noctua NH-D15 
CoolingOSPowerCase
Noctua NF-A14 PWM x6 Windows 10 Enterprise EVGA 750W G2 Phanteks Enthoo Luxe 
CPUMotherboardGraphicsGraphics
i7 7700K P870KM1 Nvidia GeForce GTX 1080 Nvidia GeForce GTX 1080 
RAMHard DriveOSMonitor
16GB DDR4 2133 Samsung 850 EVO 500GB Windows 10 Enterprise AUO B173QTN01.0 2560x1440p G-sync  
PowerCase
Eurocom 780W Clevo P870KM1 
  hide details  
Reply
post #2 of 14
Not trying to hijack sorry!
I recently replaced the stock cooler on my RX480 with an EVGA AIO I got for next to nothing, problem with this is that there's now no cooling on what appeared to be the chokes.
The stock heatsink didn't contact with anything other than the GPU chip itself so I put some small heatsinks on them with thermal adhesive but had my PC crash within 10 minutes of gaming, so I went and put an 80mm fan to take care of it with no issues since.

That said, I'm keen to hear some experts chime in on if there's more to cool on a GPU biggrin.gif
post #3 of 14
It's the Mosfet you need to cool.

You do not need to cool the caps, the chokes, or the PWM chips, although lower temperatures are always better.

All electronics benefit to a degree when cooled, but it's only the Mosfets that really generate enough heat as to require cooling. That's why the heatsinks on the motherboard (I think this is an Asus X99 Deluxe or Deluxe 2) are covering the Mosfet.



They need to convert the power from the power supply's voltage to the voltage that the CPU will use, which leads to some waste heat. Good Mosfets (like the IR3555M) will be able to achieve better efficiency than bad ones. The higher the current, the more the heat, although most Mosfets have a point where they reach optimal efficiency.

Quote:
Originally Posted by Vakten View Post

Not trying to hijack sorry!
I recently replaced the stock cooler on my RX480 with an EVGA AIO I got for next to nothing, problem with this is that there's now no cooling on what appeared to be the chokes.
The stock heatsink didn't contact with anything other than the GPU chip itself so I put some small heatsinks on them with thermal adhesive but had my PC crash within 10 minutes of gaming, so I went and put an 80mm fan to take care of it with no issues since.

That said, I'm keen to hear some experts chime in on if there's more to cool on a GPU biggrin.gif

You also need to cool the Mosfets on GPUs for similar reasons.

There needs to be a heatsink over the Mosfets and air blowing over the Mosfets.

Where did you put heatsinks? It is the Mosfets not the VRAM that need them. Keep the Mosfets cool, because they sometimes run hotter than the cores, especially at higher temperatures. I always look at PCBs when buying to make sure that the manufacturer has kept the Mosfets cool. There have been a few high profile failures. The EVGA GTX 1080 and 1070 did not have thermal pads to keep their Mosfets cool and a few people reported that they exploded.
Trooper Typhoon
(20 items)
 
  
CPUMotherboardGraphicsGraphics
5960X X99A XPower MSI r9 290X Lightning  MSI r9 290X Lightning 
RAMHard DriveHard DriveHard Drive
G.Skill Trident Z 32 Gb Samsung SM843T 960 GB Western Digital Caviar Black 2Tb Samsung 850 Pro 
Hard DriveOptical DriveCoolingCooling
Samsung SV843 960 GB LG WH14NS40 Cryorig R1 Ultimate 9x Gentle Typhoon 1850 rpm on case 
OSMonitorKeyboardPower
Windows 7 Pro x64 Korean 27" 2560x1440 Ducky Legend with Vortex PBT Doubleshot Backlit... EVGA 1300W G2 
CaseMouseAudioOther
Cooler Master Storm Trooper Logitech G502 Proteus Asus Xonar Essence STX Lamptron Fanatic Fan Controller  
  hide details  
Reply
Trooper Typhoon
(20 items)
 
  
CPUMotherboardGraphicsGraphics
5960X X99A XPower MSI r9 290X Lightning  MSI r9 290X Lightning 
RAMHard DriveHard DriveHard Drive
G.Skill Trident Z 32 Gb Samsung SM843T 960 GB Western Digital Caviar Black 2Tb Samsung 850 Pro 
Hard DriveOptical DriveCoolingCooling
Samsung SV843 960 GB LG WH14NS40 Cryorig R1 Ultimate 9x Gentle Typhoon 1850 rpm on case 
OSMonitorKeyboardPower
Windows 7 Pro x64 Korean 27" 2560x1440 Ducky Legend with Vortex PBT Doubleshot Backlit... EVGA 1300W G2 
CaseMouseAudioOther
Cooler Master Storm Trooper Logitech G502 Proteus Asus Xonar Essence STX Lamptron Fanatic Fan Controller  
  hide details  
Reply
post #4 of 14
Cool the MOSFET. The chokes and caps barely get warm and the PWM chip doesn't directly handle power so it shouldn't get hot.
Nothing Special
(29 items)
 
CPUMotherboardGraphicsGraphics
AMD FX-8350 ASUS 970 Pro Gaming/Aura Sapphire R9 Fury NITRO 4GB XFX Radeon HD 7850 2GB Core Edition 
RAMHard DriveHard DriveHard Drive
Kingston HyperX FURY 16GB DDR3L-1600 HGST Ultrastar 7K3000 2TB Kingston SSDNow V300 120GB Seagate Momentus XT 500GB 
Hard DriveHard DriveOptical DriveCooling
Crucial MX300 525GB Seagate Expansion 4TB External Sony BWU-500S Thermalright Macho X2 
CoolingCoolingCoolingCooling
CRYORIG R1 Ultimate Cougar Vortex 140mm (HDB) Phanteks PH-F140MP Fractal Design HP14-PWM 
CoolingCoolingCoolingOS
Phanteks PH-F140MP Noctua NF-A4x10 Thermalright TY-140 Windows 10 Pro 
MonitorKeyboardPowerCase
Acer XF240H Corsair K65 LUX RGB Cherry MX Red Thermaltake Tough Power DPS Gold 750W Phanteks Enthoo EVOLV ATX TG (Silver) 
MouseMouse PadAudioAudio
Steelseries Rival 700 Pecham Extended Mousepad Blue Snowball (black) Superlux HD668B 
Other
CableMod Basic ModFlex™ Cable Extension Kit - D... 
  hide details  
Reply
Nothing Special
(29 items)
 
CPUMotherboardGraphicsGraphics
AMD FX-8350 ASUS 970 Pro Gaming/Aura Sapphire R9 Fury NITRO 4GB XFX Radeon HD 7850 2GB Core Edition 
RAMHard DriveHard DriveHard Drive
Kingston HyperX FURY 16GB DDR3L-1600 HGST Ultrastar 7K3000 2TB Kingston SSDNow V300 120GB Seagate Momentus XT 500GB 
Hard DriveHard DriveOptical DriveCooling
Crucial MX300 525GB Seagate Expansion 4TB External Sony BWU-500S Thermalright Macho X2 
CoolingCoolingCoolingCooling
CRYORIG R1 Ultimate Cougar Vortex 140mm (HDB) Phanteks PH-F140MP Fractal Design HP14-PWM 
CoolingCoolingCoolingOS
Phanteks PH-F140MP Noctua NF-A4x10 Thermalright TY-140 Windows 10 Pro 
MonitorKeyboardPowerCase
Acer XF240H Corsair K65 LUX RGB Cherry MX Red Thermaltake Tough Power DPS Gold 750W Phanteks Enthoo EVOLV ATX TG (Silver) 
MouseMouse PadAudioAudio
Steelseries Rival 700 Pecham Extended Mousepad Blue Snowball (black) Superlux HD668B 
Other
CableMod Basic ModFlex™ Cable Extension Kit - D... 
  hide details  
Reply
post #5 of 14
Thread Starter 
Quote:
Originally Posted by CrazyElf View Post

It's the Mosfet you need to cool.

You do not need to cool the caps, the chokes, or the PWM chips, although lower temperatures are always better.

All electronics benefit to a degree when cooled, but it's only the Mosfets that really generate enough heat as to require cooling. That's why the heatsinks on the motherboard (I think this is an Asus X99 Deluxe or Deluxe 2) are covering the Mosfet.



They need to convert the power from the power supply's voltage to the voltage that the CPU will use, which leads to some waste heat. Good Mosfets (like the IR3555M) will be able to achieve better efficiency than bad ones. The higher the current, the more the heat, although most Mosfets have a point where they reach optimal efficiency.
You also need to cool the Mosfets on GPUs for similar reasons.

There needs to be a heatsink over the Mosfets and air blowing over the Mosfets.

Where did you put heatsinks? It is the Mosfets not the VRAM that need them. Keep the Mosfets cool, because they sometimes run hotter than the cores, especially at higher temperatures. I always look at PCBs when buying to make sure that the manufacturer has kept the Mosfets cool. There have been a few high profile failures. The EVGA GTX 1080 and 1070 did not have thermal pads to keep their Mosfets cool and a few people reported that they exploded.

Ok I will try to cool them.

With a small PCB, will the chokes radiate heat enough to affect the surrounding components?



Oh and how about those tiny rectangles on the left of the chokes?

紅魔館
(12 items)
 
秋山 澪
(10 items)
 
For Sale: Crucial 2x8GB DDR4 2400 / 1TB 2.5" HDD
$40 (USD) or best offer
CPUMotherboardGraphicsRAM
i7 5820K ASUS X99 Deluxe Zotac GTX 1080 AMP! Crucial Ballistix Sport 4x4G DDR4-2400 
Hard DriveHard DriveOptical DriveCooling
WD Black 4TB Samsung 850 EVO 1TB Dell CH30N BD-Read Noctua NH-D15 
CoolingOSPowerCase
Noctua NF-A14 PWM x6 Windows 10 Enterprise EVGA 750W G2 Phanteks Enthoo Luxe 
CPUMotherboardGraphicsGraphics
i7 7700K P870KM1 Nvidia GeForce GTX 1080 Nvidia GeForce GTX 1080 
RAMHard DriveOSMonitor
16GB DDR4 2133 Samsung 850 EVO 500GB Windows 10 Enterprise AUO B173QTN01.0 2560x1440p G-sync  
PowerCase
Eurocom 780W Clevo P870KM1 
  hide details  
Reply
紅魔館
(12 items)
 
秋山 澪
(10 items)
 
For Sale: Crucial 2x8GB DDR4 2400 / 1TB 2.5" HDD
$40 (USD) or best offer
CPUMotherboardGraphicsRAM
i7 5820K ASUS X99 Deluxe Zotac GTX 1080 AMP! Crucial Ballistix Sport 4x4G DDR4-2400 
Hard DriveHard DriveOptical DriveCooling
WD Black 4TB Samsung 850 EVO 1TB Dell CH30N BD-Read Noctua NH-D15 
CoolingOSPowerCase
Noctua NF-A14 PWM x6 Windows 10 Enterprise EVGA 750W G2 Phanteks Enthoo Luxe 
CPUMotherboardGraphicsGraphics
i7 7700K P870KM1 Nvidia GeForce GTX 1080 Nvidia GeForce GTX 1080 
RAMHard DriveOSMonitor
16GB DDR4 2133 Samsung 850 EVO 500GB Windows 10 Enterprise AUO B173QTN01.0 2560x1440p G-sync  
PowerCase
Eurocom 780W Clevo P870KM1 
  hide details  
Reply
post #6 of 14
The tiny rectangles? Look like RAM rectangles. Usually they have some thermal pads on them that mate to the heatsink. At least on most GPUs.
post #7 of 14
Quote:
Originally Posted by TK421 View Post

Ok I will try to cool them.

With a small PCB, will the chokes radiate heat enough to affect the surrounding components?



Oh and how about those tiny rectangles on the left of the chokes?


Those are capacitors. They don't need cooling. It's the squares to the right, the Mosfets that need cooling.

Quote:
Originally Posted by MicroCat View Post

The tiny rectangles? Look like RAM rectangles. Usually they have some thermal pads on them that mate to the heatsink. At least on most GPUs.


See my answer above.

They aren't RAM. The RAM is surrounding the GPU and are the big rectangles.

There's 11 of them (one of them has been deleted on the GTX 1080Ti as unlike the Titan X Pascal which has 12GB, the 1080Ti has 11GB).
Edited by CrazyElf - 4/11/17 at 8:39pm
Trooper Typhoon
(20 items)
 
  
CPUMotherboardGraphicsGraphics
5960X X99A XPower MSI r9 290X Lightning  MSI r9 290X Lightning 
RAMHard DriveHard DriveHard Drive
G.Skill Trident Z 32 Gb Samsung SM843T 960 GB Western Digital Caviar Black 2Tb Samsung 850 Pro 
Hard DriveOptical DriveCoolingCooling
Samsung SV843 960 GB LG WH14NS40 Cryorig R1 Ultimate 9x Gentle Typhoon 1850 rpm on case 
OSMonitorKeyboardPower
Windows 7 Pro x64 Korean 27" 2560x1440 Ducky Legend with Vortex PBT Doubleshot Backlit... EVGA 1300W G2 
CaseMouseAudioOther
Cooler Master Storm Trooper Logitech G502 Proteus Asus Xonar Essence STX Lamptron Fanatic Fan Controller  
  hide details  
Reply
Trooper Typhoon
(20 items)
 
  
CPUMotherboardGraphicsGraphics
5960X X99A XPower MSI r9 290X Lightning  MSI r9 290X Lightning 
RAMHard DriveHard DriveHard Drive
G.Skill Trident Z 32 Gb Samsung SM843T 960 GB Western Digital Caviar Black 2Tb Samsung 850 Pro 
Hard DriveOptical DriveCoolingCooling
Samsung SV843 960 GB LG WH14NS40 Cryorig R1 Ultimate 9x Gentle Typhoon 1850 rpm on case 
OSMonitorKeyboardPower
Windows 7 Pro x64 Korean 27" 2560x1440 Ducky Legend with Vortex PBT Doubleshot Backlit... EVGA 1300W G2 
CaseMouseAudioOther
Cooler Master Storm Trooper Logitech G502 Proteus Asus Xonar Essence STX Lamptron Fanatic Fan Controller  
  hide details  
Reply
post #8 of 14
Quote:
Originally Posted by CrazyElf View Post

Those are capacitors. They don't need cooling. It's the squares to the right, the Mosfets that need cooling.
See my answer above.

They aren't RAM. The RAM is surrounding the GPU and are the big rectangles.

There's 11 of them (one of them has been deleted on the GTX 1080Ti as unlike the Titan X Pascal which has 12GB, the 1080Ti has 11GB).

The big rectangles were very small on my screen. ;-)
post #9 of 14
chokes will rise its resistance as the temp goes up. it will be good if you could cool the choke down too. but if you don't overclock, it will be fine without any additional heatsink. but for the mosfets, it's must.

cooling the choke will also insure the choke's lifespan. but i never seen a choke failed on standard use
Pinkybeast
(19 items)
 
Mobility
(6 items)
 
 
CPUMotherboardGraphicsRAM
AMD Ryzen 7 1700X PRIME X370-PRO Sapphire RX 480 Nitro+ 4GB G-Skill F4-2400C15-16GVR 
Hard DriveHard DriveHard DriveHard Drive
Samsung 950 Pro 512GB M.2 Western Digital WD4004FZWX Seagate ST3500418AS Toshiba MK5059GSXP 
Hard DriveOptical DriveCoolingOS
Hitachi HDS721025CLA382 Asus BW-16D1HT Noctua NH-U12P SE2 Microsoft Windows 10 
MonitorKeyboardPowerCase
LG IPS LED 22MP68 generic Corsair CX600 BeQuiet Dark Base 900 Pro 
MouseMouse PadAudio
Logitech G402 Corsair MM300 Parasound Z-DAC v.2 
CPURAMHard DriveOS
AMD A6-5350M Patriot DDR3 1600 Sandisk SSD 64GB Microsoft Windows 10 Pro 
MonitorCase
17" HP Pavilion 17 e011nr 
  hide details  
Reply
Pinkybeast
(19 items)
 
Mobility
(6 items)
 
 
CPUMotherboardGraphicsRAM
AMD Ryzen 7 1700X PRIME X370-PRO Sapphire RX 480 Nitro+ 4GB G-Skill F4-2400C15-16GVR 
Hard DriveHard DriveHard DriveHard Drive
Samsung 950 Pro 512GB M.2 Western Digital WD4004FZWX Seagate ST3500418AS Toshiba MK5059GSXP 
Hard DriveOptical DriveCoolingOS
Hitachi HDS721025CLA382 Asus BW-16D1HT Noctua NH-U12P SE2 Microsoft Windows 10 
MonitorKeyboardPowerCase
LG IPS LED 22MP68 generic Corsair CX600 BeQuiet Dark Base 900 Pro 
MouseMouse PadAudio
Logitech G402 Corsair MM300 Parasound Z-DAC v.2 
CPURAMHard DriveOS
AMD A6-5350M Patriot DDR3 1600 Sandisk SSD 64GB Microsoft Windows 10 Pro 
MonitorCase
17" HP Pavilion 17 e011nr 
  hide details  
Reply
post #10 of 14
Thread Starter 
Quote:
Originally Posted by sakae48 View Post

chokes will rise its resistance as the temp goes up. it will be good if you could cool the choke down too. but if you don't overclock, it will be fine without any additional heatsink. but for the mosfets, it's must.

cooling the choke will also insure the choke's lifespan. but i never seen a choke failed on standard use

What negative things would happen if the choke resistance goes up?
紅魔館
(12 items)
 
秋山 澪
(10 items)
 
For Sale: Crucial 2x8GB DDR4 2400 / 1TB 2.5" HDD
$40 (USD) or best offer
CPUMotherboardGraphicsRAM
i7 5820K ASUS X99 Deluxe Zotac GTX 1080 AMP! Crucial Ballistix Sport 4x4G DDR4-2400 
Hard DriveHard DriveOptical DriveCooling
WD Black 4TB Samsung 850 EVO 1TB Dell CH30N BD-Read Noctua NH-D15 
CoolingOSPowerCase
Noctua NF-A14 PWM x6 Windows 10 Enterprise EVGA 750W G2 Phanteks Enthoo Luxe 
CPUMotherboardGraphicsGraphics
i7 7700K P870KM1 Nvidia GeForce GTX 1080 Nvidia GeForce GTX 1080 
RAMHard DriveOSMonitor
16GB DDR4 2133 Samsung 850 EVO 500GB Windows 10 Enterprise AUO B173QTN01.0 2560x1440p G-sync  
PowerCase
Eurocom 780W Clevo P870KM1 
  hide details  
Reply
紅魔館
(12 items)
 
秋山 澪
(10 items)
 
For Sale: Crucial 2x8GB DDR4 2400 / 1TB 2.5" HDD
$40 (USD) or best offer
CPUMotherboardGraphicsRAM
i7 5820K ASUS X99 Deluxe Zotac GTX 1080 AMP! Crucial Ballistix Sport 4x4G DDR4-2400 
Hard DriveHard DriveOptical DriveCooling
WD Black 4TB Samsung 850 EVO 1TB Dell CH30N BD-Read Noctua NH-D15 
CoolingOSPowerCase
Noctua NF-A14 PWM x6 Windows 10 Enterprise EVGA 750W G2 Phanteks Enthoo Luxe 
CPUMotherboardGraphicsGraphics
i7 7700K P870KM1 Nvidia GeForce GTX 1080 Nvidia GeForce GTX 1080 
RAMHard DriveOSMonitor
16GB DDR4 2133 Samsung 850 EVO 500GB Windows 10 Enterprise AUO B173QTN01.0 2560x1440p G-sync  
PowerCase
Eurocom 780W Clevo P870KM1 
  hide details  
Reply
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Air Cooling
Overclock.net › Forums › Cooling › Air Cooling › What part of a VRM should I cool?