Overclock.net › Forums › AMD › AMD - General › VRM on the new AM4 motherboards
New Posts  All Forums:Forum Nav:

VRM on the new AM4 motherboards - Page 93

post #921 of 1994
Quote:
Originally Posted by chew* View Post

Your talking 50% less pwm heatsink on those boards prime pro included.....

bad comparison is a bad comparison.

Socket voltage will come out sooner or later.......either by myself or someone else.

If you trust hw monitor? sure I can easily beat those temps at hotter ambients with less heatsink and more voltage......

Not hard to shove fans behind PCB or over vrm and say hey look my pwm runs cool......

well... they would be cooler tongue.gif
post #922 of 1994
Ryzen - Mythbusters R5/Taichi edition how to 32g dual rank.
https://youtu.be/MwM7HmREc5Y
post #923 of 1994
Workstation stuff
(407 photos)
SpecViewperf 12.0.1
(117 photos)
PGA 1331
(13 items)
 
CPUMotherboardGraphicsRAM
AMD Zen SR7 octocore (Ryzen 7 1700) Overclockable AM4 motherboard X370 To be determined , AMD Vega? 2x8GB DDR4 low-profile or heatsink-less 
Hard DriveHard DriveCoolingCooling
Samsung 950 Pro / 960 Evo / 960 Pro 256GB or 51... Samsung 850 Evo 1TB SSD Storage Black or black+white Twin tower air cooler or s... EK Vardar F2-140 140mm, Phanteks PH-F140SP 140m... 
CoolingOSMonitorPower
Fractal Design Dynamic GP14 (included with case) Win 10 Pro 64 bit 4K monitor with Freesync EVGA Supernova G3/P2 750W or 850W 
Case
Fractal Design Define R5 Blackout edition 
  hide details  
Reply
Workstation stuff
(407 photos)
SpecViewperf 12.0.1
(117 photos)
PGA 1331
(13 items)
 
CPUMotherboardGraphicsRAM
AMD Zen SR7 octocore (Ryzen 7 1700) Overclockable AM4 motherboard X370 To be determined , AMD Vega? 2x8GB DDR4 low-profile or heatsink-less 
Hard DriveHard DriveCoolingCooling
Samsung 950 Pro / 960 Evo / 960 Pro 256GB or 51... Samsung 850 Evo 1TB SSD Storage Black or black+white Twin tower air cooler or s... EK Vardar F2-140 140mm, Phanteks PH-F140SP 140m... 
CoolingOSMonitorPower
Fractal Design Dynamic GP14 (included with case) Win 10 Pro 64 bit 4K monitor with Freesync EVGA Supernova G3/P2 750W or 850W 
Case
Fractal Design Define R5 Blackout edition 
  hide details  
Reply
post #924 of 1994
Quote:
Originally Posted by DADDYDC650 View Post

Overpriced VRM design on the MSI Titanium? Ouch!

I keep hearing how inefficient this design is and yet it performs better than the Gigabyte design he touts in comparison...and is only a *hair* behind the CH6. The wattage measurements were taken *at the wall*, not with software. Still waiting on an explanation. I know Chew's response, but *at the wall*...so I don't want to hear excuses about software or calibration...

http://www.kitguru.net/components/motherboard/luke-hill/msi-x370-xpower-gaming-titanium-motherboard-review/10/
Warning: Spoiler! (Click to show)

By the way, my question is serious. Somebody must be missing something, and I think it is in everyone's interest to understand what it is...
post #925 of 1994
You really need to dig deep when comparing stock...vrm settings by default llc @ default.

Onboard devices or lack of.

Its really tough to make an accurate assessment.

Just a couple examples. Ch6 memory vrm runs @ extreme by default.

Taichi has wifi/bt on by default.

Just examples.

Tough call tbh
Edited by chew* - 4/16/17 at 8:44pm
post #926 of 1994
Quote:
Originally Posted by TheOldTechGuru View Post

I keep hearing how inefficient this design is and yet it performs better than the Gigabyte design he touts in comparison...and is only a *hair* behind the CH6. The wattage measurements were taken *at the wall*, not with software. Still waiting on an explanation. I know Chew's response, but *at the wall*...so I don't want to hear excuses about software or calibration...

http://www.kitguru.net/components/motherboard/luke-hill/msi-x370-xpower-gaming-titanium-motherboard-review/10/
Warning: Spoiler! (Click to show)

By the way, my question is serious. Somebody must be missing something, and I think it is in everyone's interest to understand what it is...

Last I heard there was more on a motherboard than the vrm. Components not present on one board obviously aren't going to show up as power draw. . This would in theory result in lower power measured at the wall. This was laid out the last time the argument was made that power at wall meant vrm was more efficent. So unless you want to be the one who goes over the competing boards feature by feature, calculates power draws at load and then does the math....

As for temps, vrm cooling on that board is possibly the best. Better than competitors.

So.. more power in to one subsystem to get same power to cpu = performing product.

It can do that and still draw less power at the wall than a board with other things, that it doesn't have, drawing power, or it could just be so much more efficient elsewhere that it draws less power at the wall despite using more in one subsystem. Neither is irreconcilable with the less expensive parts. They do their job.

Putting a dmm on that socket won't prove they're more efficient, or less. It'll just prove that there's a difference in what software is reporting vs what gets to the cpu and that happens with just about every motherboard.The motherboard won't care, it'll keep doing it's job. But you'll know. Maybe squeeze a bit more performance out


Or you could be like cssorkinman who's motherboard won't care.when if it learns the software that reports it's voltage's is off by x amount. It'll just keep trucking along at 4.0 with 3200 and his horrible 15 minute set up time. I feel his pain. Must be terrible.. bears it well.
post #927 of 1994
Quote:
Originally Posted by yendor View Post

Last I heard there was more on a motherboard than the vrm. Components not present on one board obviously aren't going to show up as power draw. . This would in theory result in lower power measured at the wall. This was laid out the last time the argument was made that power at wall meant vrm was more efficent. So unless you want to be the one who goes over the competing boards feature by feature, calculates power draws at load and then does the math....

As for temps, vrm cooling on that board is possibly the best. Better than competitors.

So.. more power in to one subsystem to get same power to cpu = performing product.

It can do that and still draw less power at the wall than a board with other things, that it doesn't have, drawing power, or it could just be so much more efficient elsewhere that it draws less power at the wall despite using more in one subsystem. Neither is irreconcilable with the less expensive parts. They do their job.

Putting a dmm on that socket won't prove they're more efficient, or less. It'll just prove that there's a difference in what software is reporting vs what gets to the cpu and that happens with just about every motherboard.The motherboard won't care, it'll keep doing it's job. But you'll know. Maybe squeeze a bit more performance out


Or you could be like cssorkinman who's motherboard won't care.when if it learns the software that reports it's voltage's is off by x amount. It'll just keep trucking along at 4.0 with 3200 and his horrible 15 minute set up time. I feel his pain. Must be terrible.. bears it well.

VRM's use up the most power of any subsystem by far, except the GPU. Neither the CH6 nor the Gigabyte are loaded with extra features compared to the Titanium. I agree with the VRM cooling, but that impacts temp not power draw. I don't know if anyone here really has an answer, but it is something I am truly curious about.

I am also curious as to how Buildzoid came up with 252 amps for the Titanium VRM when the PK616BAs are rated at 50A each? Thats 300 amps. I watched one of his other reviews and he used the full rated current for that calculation. He also assumes only 300 Khz switching even though the mosfet is rated for 1 Mhz. I have been reading up a LOT on VRM's and from what I can find the Low-side is *much* more critical. He does note that running the two PK632BA's in parallel yields 1/2 the resistance but stops short of following through on that - 1.5 milliohms, which puts the effective resistance down to the level of the best (NextFET rated at 1.2) but a current capacity of 78 amps each - yielding nearly the effective efficiency with a higher package current capacity.

The response curves for all of these are non-linear and I keep seeing 125c assumptions. Since we aren't seeing anywhere near those temps on the better boards it just seems to me the electronic engineers may have known what they were doing and designed circuits to work within their sweet spot *even when overclocking*, yielding better than assumed performance; not just for the Titanium but for any of the better boards. It reminds of wire gauge and current. Where you may need 14 gauge solid wire for a given current load, 16 gauge may be better in some applications if using stranded wire because current flows on the surface...the devil is in the details...

This isn't an attempt to explain so much as to understand...kind of thinking through the process of understanding "out-loud". This may very well be beyond what most would bother with, but I do prefer to *really* understand what is going on rather than just accept over-simplified answers - but I am not an electronics engineer and my understanding remains superficial still.
post #928 of 1994
Quote:
Originally Posted by TheOldTechGuru View Post

VRM's use up the most power of any subsystem by far, except the GPU. Neither the CH6 nor the Gigabyte are loaded with extra features compared to the Titanium. I agree with the VRM cooling, but that impacts temp not power draw. I don't know if anyone here really has an answer, but it is something I am truly curious about.

I am also curious as to how Buildzoid came up with 252 amps for the Titanium VRM when the PK616BAs are rated at 50A each? Thats 300 amps. I watched one of his other reviews and he used the full rated current for that calculation. He also assumes only 300 Khz switching even though the mosfet is rated for 1 Mhz. I have been reading up a LOT on VRM's and from what I can find the Low-side is *much* more critical. He does note that running the two PK632BA's in parallel yields 1/2 the resistance but stops short of following through on that - 1.5 milliohms, which puts the effective resistance down to the level of the best (NextFET rated at 1.2) but a current capacity of 78 amps each - yielding nearly the effective efficiency with a higher package current capacity.

The response curves for all of these are non-linear and I keep seeing 125c assumptions. Since we aren't seeing anywhere near those temps on the better boards it just seems to me the electronic engineers may have known what they were doing and designed circuits to work within their sweet spot *even when overclocking*, yielding better than assumed performance; not just for the Titanium but for any of the better boards. It reminds of wire gauge and current. Where you may need 14 gauge solid wire for a given current load, 16 gauge may be better in some applications if using stranded wire because current flows on the surface...the devil is in the details...

This isn't an attempt to explain so much as to understand...kind of thinking through the process of understanding "out-loud". This may very well be beyond what most would bother with, but I do prefer to *really* understand what is going on rather than just accept over-simplified answers - but I am not an electronics engineer and my understanding remains superficial still.

Buildzoid is using worst case scenario for temperatures and it makes sense as this way you can see what kind of current you can drive in the worst possible case scenario without the VRM dying, the 50A rating per mosfet on the NIKOs is at TCase temperature of 25C at TCase 100C that rating drops down to 31.5A at 125C that amperage rating is going to drop even lower. As for the switching frequency he is assuming what is typically used on Motherboards by most manufactures, as stated in the video he doesn't know for sure if that is the switching frequency since he doesn't have an actual sample board to test with, so he is letting the audience know this is what my assumption is.
Mini PC
(14 items)
 
  
CPUMotherboardGraphicsRAM
AMD Ryzen 7 1800x Gigabyte Gaming 3 AB350M ASUS Radeon 290 Direct CU II OC CORSAIR Vengeance LPX 16GB (2 x 8GB) 
Hard DriveOptical DriveCoolingOS
Western Digital Blue None Noctua NH-U12S Windows 10 
PowerCase
Seasonic Flagship Prime Titanium 850 Watt Node 804 
  hide details  
Reply
Mini PC
(14 items)
 
  
CPUMotherboardGraphicsRAM
AMD Ryzen 7 1800x Gigabyte Gaming 3 AB350M ASUS Radeon 290 Direct CU II OC CORSAIR Vengeance LPX 16GB (2 x 8GB) 
Hard DriveOptical DriveCoolingOS
Western Digital Blue None Noctua NH-U12S Windows 10 
PowerCase
Seasonic Flagship Prime Titanium 850 Watt Node 804 
  hide details  
Reply
post #929 of 1994
Quote:
Originally Posted by Zhany View Post

Buildzoid is using worst case scenario for temperatures and it makes sense as this way you can see what kind of current you can drive in the worst possible case scenario without the VRM dying, the 50A rating per mosfet on the NIKOs is at TCase temperature of 25C at TCase 100C that rating drops down to 31.5A at 125C that amperage rating is going to drop even lower. As for the switching frequency he is assuming what is typically used on Motherboards by most manufactures, as stated in the video he doesn't know for sure if that is the switching frequency since he doesn't have an actual sample board to test with, so he is letting the audience know this is what my assumption is.

I get that, but on his other videos the current rating he gives is the rating at 25c, not 125c...

https://youtu.be/3xfLYLRsPZ0?t=303

He shows 40A at 125c, but the spec sheet shows that being the 25c current rating. Below the current rating they show an operating temp of 125c, but that is a different spec and they are not related. The top of the spec sheet clearly states t=25c unless otherwise noted. The current vs temp graph shows less than 30 amps at 85c...

http://www.ti.com/lit/ds/symlink/csd87350q5d.pdf

(pg 5, Figure 4, second graph on the right hand side). And actually, figure 5 shows current dropping like a rock at 120c if using board temp instead of ambient. So it could be lower than 10A at 125c...but that would make that chip look really bad.

So he is inconsistent with his analysis... :-(

Hard to put too much faith in someone who cannot properly read a spec sheet.
Edited by TheOldTechGuru - 4/17/17 at 8:36am
post #930 of 1994
Quote:
Originally Posted by TheOldTechGuru View Post

I get that, but on his other videos the current rating he gives is the rating at 25c, not 125c...

https://youtu.be/3xfLYLRsPZ0?t=303

He shows 40A at 125c, but the spec sheet shows that being the 25c current rating. Below the current rating they show an operating temp of 125c, but that is a different spec and they are not related. The top of the spec sheet clearly states t=25c unless otherwise noted. The current vs temp graph shows less than 30 amps at 85c...

http://www.ti.com/lit/ds/symlink/csd87350q5d.pdf

(pg 5, second graph on the right hand side).

So he is inconsistent with his analysis... :-(

Hard to put too much faith in someone who cannot properly read a spec sheet.
Still fighting for that overpriced MSI Titanium board I see?
Gaming PC
(17 items)
 
  
CPUMotherboardGraphicsRAM
AMD RYZEN R7 1800X @4Ghz Asrock x370 Fatal1ty Professional Nvidia GTX 1080 G.SKILL TridentZ RGB Series 16GB (2 x 8GB) 3200... 
Hard DriveHard DriveHard DriveCooling
Samsung 840 Pro 256GB SSD Samsung 850 Pro 512GB SSD Samsung 850 EVO 1TB SSD Corsair H100i 
OSMonitorKeyboardPower
Microsoft Windows 10 Pro 64-bit Samsung 49KS8000 Corsair K70 RGB Corsair AX1200i 
CaseMouseMouse PadAudio
Cooler Master Mastercase Maker 5  Corsair M65 RGB Custom SF 49ERS mouse pad Philips X1 headphones with V-MODA BoomPro mic 
Audio
Sound BlasterX Katana 
  hide details  
Reply
Gaming PC
(17 items)
 
  
CPUMotherboardGraphicsRAM
AMD RYZEN R7 1800X @4Ghz Asrock x370 Fatal1ty Professional Nvidia GTX 1080 G.SKILL TridentZ RGB Series 16GB (2 x 8GB) 3200... 
Hard DriveHard DriveHard DriveCooling
Samsung 840 Pro 256GB SSD Samsung 850 Pro 512GB SSD Samsung 850 EVO 1TB SSD Corsair H100i 
OSMonitorKeyboardPower
Microsoft Windows 10 Pro 64-bit Samsung 49KS8000 Corsair K70 RGB Corsair AX1200i 
CaseMouseMouse PadAudio
Cooler Master Mastercase Maker 5  Corsair M65 RGB Custom SF 49ERS mouse pad Philips X1 headphones with V-MODA BoomPro mic 
Audio
Sound BlasterX Katana 
  hide details  
Reply
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: AMD - General
Overclock.net › Forums › AMD › AMD - General › VRM on the new AM4 motherboards