Jump to content

PSU fan on the bottom or top?

willing
By willing
in Power Supplies
 Share
Posted

For starters, my case is a Phanteks Enthoo Evolv ITX and the PSU mounting position is on the bottom.

 

I recently opened my rig to dust it off, and I realized that I had my PSU mounted so that the fan is on the top.

Is there a noticeable difference in temperatures by mounting my PSU so the fan is on the top vs the fan being on the bottom?

 

Thank you in advance.

1) Gaming Rig: https://pcpartpicker.com/list/TZskD2

CPU: Intel Core i5-4690K @ 4.2GHz OC | Motherboard: Gigabyte Z97N-WiFi ITX | RAM: 2x8GB DDR3-1600MHz G.Skill Ripjaws X-series | GPU: EVGA GTX 1070 Ti SC @ 1817MHz OC

PSU: EVGA 650W G2 80+ Gold | Case: Phanteks Enthoo Evolv ITX | Cooler: Cooler Master Hyper 212 Evo w/ Noctua NF-F12 Fan | SSD: Samsung 850 EVO 250GB | HDD: WD Blue 2TB

Monitor: Dell S2417DG 1440p @ 144Hz w/ G-Sync | Speakers: M-Audio Studiophile AV40 | Keyboard: Corsair K65 Compact Cherry MX Red | Mouse: Logitech G402 Hyperion Fury

 

2) Digital Forensics Rig: https://pcpartpicker.com/list/sWV7w6

CPU: 2x Intel Xeon E5-2650 v3 @ 2.3GHz | Motherboard: ASRock EP2C612D16-4L | RAM: 8x16GB DDR4-2133MHz Samsung ECC Server Memory

PSU: EVGA 1200W P2 80+ Platnium | Case: Phanteks Enthoo Primo | Cooler: 2x Noctua NH-U9DX i4 | SSD: Samsung 960 PRO 1TB | HDD: 4x WD Red 4TB

Monitor: 2x LG25UM56-P 2560x1080p @ 60Hz

Link to comment
Share on other sites
Link to post
Share on other sites
Posted

I have the Phanteks Enthoo Pro case and my PSU is facing downwards so the GPU doesn't have to fight for air, and it does make a slight difference.

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
  • Author

I switched the orientation of my PSU so the fan is facing the bottom and did some temp tests again, only saw like 1C difference. I guess it's something.

1) Gaming Rig: https://pcpartpicker.com/list/TZskD2

CPU: Intel Core i5-4690K @ 4.2GHz OC | Motherboard: Gigabyte Z97N-WiFi ITX | RAM: 2x8GB DDR3-1600MHz G.Skill Ripjaws X-series | GPU: EVGA GTX 1070 Ti SC @ 1817MHz OC

PSU: EVGA 650W G2 80+ Gold | Case: Phanteks Enthoo Evolv ITX | Cooler: Cooler Master Hyper 212 Evo w/ Noctua NF-F12 Fan | SSD: Samsung 850 EVO 250GB | HDD: WD Blue 2TB

Monitor: Dell S2417DG 1440p @ 144Hz w/ G-Sync | Speakers: M-Audio Studiophile AV40 | Keyboard: Corsair K65 Compact Cherry MX Red | Mouse: Logitech G402 Hyperion Fury

 

2) Digital Forensics Rig: https://pcpartpicker.com/list/sWV7w6

CPU: 2x Intel Xeon E5-2650 v3 @ 2.3GHz | Motherboard: ASRock EP2C612D16-4L | RAM: 8x16GB DDR4-2133MHz Samsung ECC Server Memory

PSU: EVGA 1200W P2 80+ Platnium | Case: Phanteks Enthoo Primo | Cooler: 2x Noctua NH-U9DX i4 | SSD: Samsung 960 PRO 1TB | HDD: 4x WD Red 4TB

Monitor: 2x LG25UM56-P 2560x1080p @ 60Hz

Link to comment
Share on other sites
Link to post
Share on other sites
Posted

the advantage of having the PSU fan pointing downwards is to reduce amount of dust getting in. You technically can, but shouldnt open up a PSU and clean the insides.

CPU: i7-2600K 4751MHz 1.44V (software) --> 1.47V at the back of the socket Motherboard: Asrock Z77 Extreme4 (BCLK: 103.3MHz) CPU Cooler: Noctua NH-D15 RAM: Adata XPG 2x8GB DDR3 (XMP: 2133MHz 10-11-11-30 CR2, custom: 2203MHz 10-11-10-26 CR1 tRFC:230 tREFI:14000) GPU: Asus GTX 1070 Dual (Super Jetstream vbios, +70(2025-2088MHz)/+400(8.8Gbps)) SSD: Samsung 840 Pro 256GB (main boot drive), Transcend SSD370 128GB PSU: Seasonic X-660 80+ Gold Case: Antec P110 Silent, 5 intakes 1 exhaust Monitor: AOC G2460PF 1080p 144Hz (150Hz max w/ DP, 121Hz max w/ HDMI) TN panel Keyboard: Logitech G610 Orion (Cherry MX Blue) with SteelSeries Apex M260 keycaps Mouse: BenQ Zowie FK1

 

Model: HP Omen 17 17-an110ca CPU: i7-8750H (0.125V core & cache, 50mV SA undervolt) GPU: GTX 1060 6GB Mobile (+80/+450, 1650MHz~1750MHz 0.78V~0.85V) RAM: 8+8GB DDR4-2400 18-17-17-39 2T Storage: HP EX920 1TB PCIe x4 M.2 SSD + Crucial MX500 1TB 2.5" SATA SSD, 128GB Toshiba PCIe x2 M.2 SSD (KBG30ZMV128G) gone cooking externally, 1TB Seagate 7200RPM 2.5" HDD (ST1000LM049-2GH172) left outside Monitor: 1080p 126Hz IPS G-sync

 

Desktop benching:

Cinebench R15 Single thread:168 Multi-thread: 833 

SuperPi (v1.5 from Techpowerup, PI value output) 16K: 0.100s 1M: 8.255s 32M: 7m 45.93s

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
  • Author

@Jurrunio 1C difference vs less dust getting in...I will have my PSU fan facing down.

Thank you for your comment.

1) Gaming Rig: https://pcpartpicker.com/list/TZskD2

CPU: Intel Core i5-4690K @ 4.2GHz OC | Motherboard: Gigabyte Z97N-WiFi ITX | RAM: 2x8GB DDR3-1600MHz G.Skill Ripjaws X-series | GPU: EVGA GTX 1070 Ti SC @ 1817MHz OC

PSU: EVGA 650W G2 80+ Gold | Case: Phanteks Enthoo Evolv ITX | Cooler: Cooler Master Hyper 212 Evo w/ Noctua NF-F12 Fan | SSD: Samsung 850 EVO 250GB | HDD: WD Blue 2TB

Monitor: Dell S2417DG 1440p @ 144Hz w/ G-Sync | Speakers: M-Audio Studiophile AV40 | Keyboard: Corsair K65 Compact Cherry MX Red | Mouse: Logitech G402 Hyperion Fury

 

2) Digital Forensics Rig: https://pcpartpicker.com/list/sWV7w6

CPU: 2x Intel Xeon E5-2650 v3 @ 2.3GHz | Motherboard: ASRock EP2C612D16-4L | RAM: 8x16GB DDR4-2133MHz Samsung ECC Server Memory

PSU: EVGA 1200W P2 80+ Platnium | Case: Phanteks Enthoo Primo | Cooler: 2x Noctua NH-U9DX i4 | SSD: Samsung 960 PRO 1TB | HDD: 4x WD Red 4TB

Monitor: 2x LG25UM56-P 2560x1080p @ 60Hz

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
2 hours ago, Jurrunio said:

the advantage of having the PSU fan pointing downwards is to reduce amount of dust getting in. 

Dust getting in where?  The PSU?

 

If the fan is pointing down, it's literally sucking air right off the floor.

 

I honestly have ZERO good reason for suggesting mounting a PSU either fan up or fan down.  If you have liquid cooling, however, I suggest fan down in case you spring a leak.  Wouldn't want coolant to drip into your PSU.

 

 

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
2 minutes ago, jonnyGURU said:

Dust getting in where?  The PSU?

 

If the fan is pointing down, it's literally sucking air right off the floor.

 

I honestly have ZERO good reason for suggesting mounting a PSU either fan up or fan down.  If you have liquid cooling, however, I suggest fan down in case you spring a leak.  Wouldn't want coolant to drip into your PSU.

 

 

Just looking at how much dust there is on the back of the graphics card (if it's mounted in the traditional way) can show how much dust can get in the PSU if the fan's pointing upwards. Mine do accumulate some dust even though all intakes have air filters (probably bad ones idk), that's why I recommend pointing the fan downwards. Especially at times when the PSU goes to fanless mode and doesnt pull dust in actively

CPU: i7-2600K 4751MHz 1.44V (software) --> 1.47V at the back of the socket Motherboard: Asrock Z77 Extreme4 (BCLK: 103.3MHz) CPU Cooler: Noctua NH-D15 RAM: Adata XPG 2x8GB DDR3 (XMP: 2133MHz 10-11-11-30 CR2, custom: 2203MHz 10-11-10-26 CR1 tRFC:230 tREFI:14000) GPU: Asus GTX 1070 Dual (Super Jetstream vbios, +70(2025-2088MHz)/+400(8.8Gbps)) SSD: Samsung 840 Pro 256GB (main boot drive), Transcend SSD370 128GB PSU: Seasonic X-660 80+ Gold Case: Antec P110 Silent, 5 intakes 1 exhaust Monitor: AOC G2460PF 1080p 144Hz (150Hz max w/ DP, 121Hz max w/ HDMI) TN panel Keyboard: Logitech G610 Orion (Cherry MX Blue) with SteelSeries Apex M260 keycaps Mouse: BenQ Zowie FK1

 

Model: HP Omen 17 17-an110ca CPU: i7-8750H (0.125V core & cache, 50mV SA undervolt) GPU: GTX 1060 6GB Mobile (+80/+450, 1650MHz~1750MHz 0.78V~0.85V) RAM: 8+8GB DDR4-2400 18-17-17-39 2T Storage: HP EX920 1TB PCIe x4 M.2 SSD + Crucial MX500 1TB 2.5" SATA SSD, 128GB Toshiba PCIe x2 M.2 SSD (KBG30ZMV128G) gone cooking externally, 1TB Seagate 7200RPM 2.5" HDD (ST1000LM049-2GH172) left outside Monitor: 1080p 126Hz IPS G-sync

 

Desktop benching:

Cinebench R15 Single thread:168 Multi-thread: 833 

SuperPi (v1.5 from Techpowerup, PI value output) 16K: 0.100s 1M: 8.255s 32M: 7m 45.93s

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
  • Author
29 minutes ago, jonnyGURU said:

Dust getting in where?  The PSU?

 

If the fan is pointing down, it's literally sucking air right off the floor.

 

I honestly have ZERO good reason for suggesting mounting a PSU either fan up or fan down.  If you have liquid cooling, however, I suggest fan down in case you spring a leak.  Wouldn't want coolant to drip into your PSU.

 

 

Thank you for your advice JonnyGuru. It really is preference I guess since my 1C temp difference from changing the PSU fan orientation is basically margin of error.

Love your detailed PSU reviews btw.

1) Gaming Rig: https://pcpartpicker.com/list/TZskD2

CPU: Intel Core i5-4690K @ 4.2GHz OC | Motherboard: Gigabyte Z97N-WiFi ITX | RAM: 2x8GB DDR3-1600MHz G.Skill Ripjaws X-series | GPU: EVGA GTX 1070 Ti SC @ 1817MHz OC

PSU: EVGA 650W G2 80+ Gold | Case: Phanteks Enthoo Evolv ITX | Cooler: Cooler Master Hyper 212 Evo w/ Noctua NF-F12 Fan | SSD: Samsung 850 EVO 250GB | HDD: WD Blue 2TB

Monitor: Dell S2417DG 1440p @ 144Hz w/ G-Sync | Speakers: M-Audio Studiophile AV40 | Keyboard: Corsair K65 Compact Cherry MX Red | Mouse: Logitech G402 Hyperion Fury

 

2) Digital Forensics Rig: https://pcpartpicker.com/list/sWV7w6

CPU: 2x Intel Xeon E5-2650 v3 @ 2.3GHz | Motherboard: ASRock EP2C612D16-4L | RAM: 8x16GB DDR4-2133MHz Samsung ECC Server Memory

PSU: EVGA 1200W P2 80+ Platnium | Case: Phanteks Enthoo Primo | Cooler: 2x Noctua NH-U9DX i4 | SSD: Samsung 960 PRO 1TB | HDD: 4x WD Red 4TB

Monitor: 2x LG25UM56-P 2560x1080p @ 60Hz

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
1 hour ago, jonnyGURU said:

Dust getting in where?  The PSU?

 

If the fan is pointing down, it's literally sucking air right off the floor.

 

I honestly have ZERO good reason for suggesting mounting a PSU either fan up or fan down.  If you have liquid cooling, however, I suggest fan down in case you spring a leak.  Wouldn't want coolant to drip into your PSU.

 

 

I've seen a couple cases with next to no space below the bottom, mounting the PSU face down their would have a decent chance of causing overtemp problems. 

Just some bapo nerd from 'Straya

 

PCs:

Main: i7 7700K (5GHz 1.4V) | ASUS GTX 1080 TURBO | 4x8GB Corsair Vengeance 3000MHz (3200MHz CL14 1.365V) | ASUS PRIME Z270-AR | Thermaltake SMART 750P | Coolermaster Seidon 240P | Acer Predator X34 (34" 1440p144Hz GSync IPS)

 

Secondary: i5 3570K | Intel HD4000 (RIP Sapphire HD 6850) | 2x2GB + 1x4GB Kingston 1600MHz | ASUS P8Z68-V LX | Corsair CX650 | Coolermaster Hyper D92 | Sony Bravia VPL-VW80 (108" 1080p60Hz projector)

 

Laptop: i7 7700HQ | GTX 1060 6GB MXM | 2x16GB SODIMM | OEM Acer Motherboard | 17.3" Screen (1080p60Hz IPS)

 

iMac: Core 2 Duo T7400 | ATI Radeon X1600 | 2x1GB 667MHz DDR2 | 20" Screen

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
1 hour ago, awesomegamer919 said:

I've seen a couple cases with next to no space below the bottom, mounting the PSU face down their would have a decent chance of causing overtemp problems. 

Those must be the exception, not the rule.  Most, when the PSU is right up against the bottom, at least have a fan grill for the PSU.

 

Link to comment
Share on other sites
Link to post
Share on other sites
Posted

Some chassis have no airflow (I.E. NZXT S340) for PSUs mounted with the fan-side up. It's generally better to do fan-side down.

|PSU Tier List /80 Plus Efficiency| PSU stuff if you need it. 

My system: PCPartPicker || For Corsair support tag @Corsair Josephor @Corsair Nick || My 5MT Legacy GT Wagon ||

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
18 hours ago, jonnyGURU said:

I honestly have ZERO good reason for suggesting mounting a PSU either fan up or fan down.  If you have liquid cooling, however, I suggest fan down in case you spring a leak.  Wouldn't want coolant to drip into your PSU.

I do.

With fan facing down, its highly unlikely that any foreign object might find its way into the PSU.

With fan facing up, it is highly likely...

"Hell is full of good meanings, but Heaven is full of good works"

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
9 minutes ago, Stefan Payne said:

I do.

With fan facing down, its highly unlikely that any foreign object might find its way into the PSU.

With fan facing up, it is highly likely...

Which is pretty much what I just said, isn't it? 

 

Link to comment
Share on other sites
Link to post
Share on other sites
Posted
13 hours ago, jonnyGURU said:

Which is pretty much what I just said, isn't it? 

 

You forgot possible "FOD" from dropping screw accidentally.

Better to not leave Mr. Murphy chance to cause that.

Link to comment
Share on other sites
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing Power Supplies

×