X299 VRM Disaster

[StyM]

[bluestang]

[BenchZowner]

There's a good chance Der8aur kind of screwed up on this one.

JonnyGuru pointed out that the PSU he's using has severe issues including bad quality and thin wires that suffer a whole lot of voltage drop.

[pumero]

Well, the VRM parts were quite toasty on many X79 and X99 boards too, when properly overclocked, so nothing new here.

However, he is right that the VRM coolers are a joke nowadays, as they are only there to look nice or fancy but fail to meet the basic criteria of a heatsink, which is a large surface area.
We laughed at the heatpipe circus stuff 10 years ago, but they would definitely do a better job than those useless chunks of metal currently used.

The VRM component quality doesn't seem to be particularly great either, when I look at the squeaking VRM noises in this video:
https://youtu.be/15g_XLRc3QA
Sounds a bit like an old matrix printer mixed with a FAX machine and this was just with a 7740X, not a 7900X.

[zanzabar]

There's a good chance Der8aur kind of screwed up on this one.

JonnyGuru pointed out that the PSU he's using has severe issues including bad quality and thin wires that suffer a whole lot of voltage drop.

does that matter in this case? if anything it should help the argument here if he has poor quality cables on the psu as you cannot guarantee things will work over spec. he was running at stock and skylake X when complaining, what happens with the big parts that require rack or liquid cooling.

[BenchZowner]

It does, because with lower input voltage the VRMs draw more current.

Anyway, apart from limiting the stable 24/7 air oc ( if ), temps aren't a problem warranty-wise, the mosfets are rated at at least 125C ( normally 150C+, with high end models coming in at up to 240C! )

[chew*]

There's a good chance Der8aur kind of screwed up on this one.

JonnyGuru pointed out that the PSU he's using has severe issues including bad quality and thin wires that suffer a whole lot of voltage drop.

Ok maybe that explains part of it...except he pulled vrm sinks off and got good temps after doing so.

That sort of eliminates psu no?

[BenchZowner]

Ok maybe that explains part of it...except he pulled vrm sinks off and got good temps after doing so.

That sort of eliminates psu no?

Nope, it's like graphics card overclocking and its VRM/memory chips.
Remember the old models where the stock cooler would "split" in two or more parts ?
Usually if you removed the "backplate" which was supposedly cooling the VRM & memory chips you'd get lower temps.

Those terrible heatsinks ( allow me to call them... HeatStinks ) are just gathering heat and are terrible at disposing it.

It's like taking a heatspreader to the VRM & memory and the GPU... it'll transfer heat between components and as time goes by it will raise the temps of all components.

What would've been way more effective is something we used to do in the past if you recall for VRM & Memory ICs, small copper heatsinks, each piece for each IC.

In any case, without the VRM Heatsink and with the same fan blowing them, with another PSU with proper voltages, it would've been even cooler.

[chew*]

I am guessing he was using seasonic?

I have tried 3 dinosaurs on my setups. TT toughpower 1200w (cwt) pc power and cooling ( should have been retired long ago ) and Antec TPQ 1200w.

All same results. Heatstinks suck..

[BenchZowner]

Superflower modular with the crystal clear connectors [ don't know why anyone would use that PSU ]

[chew*]

Same reason people would beat there head in PI 32m on a known slow board instead of just using the clearly faster board.

They do not want to take a wizz in there sponsors wheaties.

[BenchZowner]

Sad but true.

[Revv23]

It does, because with lower input voltage the VRMs draw more current.

Anyway, apart from limiting the stable 24/7 air oc ( if ), temps aren't a problem warranty-wise, the mosfets are rated at at least 125C ( normally 150C+, with high end models coming in at up to 240C! )

More amps at less volts is the same current as more volts as less amps. Volts * amps = watts. Never heard of a power supply affecting temps before. Certainly clean power into the VRM will get better power into CPU, better the VRM design the less that matters.

Anyone here been around long enough to remember the plastic "air channel" shroud on the Abit IC7-G? Had lots of tiny little heatsinks in my toolbox then. HiPro's modding guide on that board got me into OC.

Wasn't that annoying to mod the hell out of the board when it wasn't pushing 400 bux.

[BenchZowner]

More amps at less volts is the same current as more volts as less amps. Volts * amps = watts. Never heard of a power supply affecting temps before. Certainly clean power into the VRM will get better power into CPU, better the VRM design the less that matters.

Anyone here been around long enough to remember the plastic "air channel" shroud on the Abit IC7-G? Had lots of tiny little heatsinks in my toolbox then. HiPro's modding guide on that board got me into OC.

Wasn't that annoying to mod the hell out of the board when it wasn't pushing 400 bux.

You are missing the point.

1) Lower driving voltage = mosfets operate at sub-optimal efficiency ( hint: worse efficiency = not as clean output, and more power gone to waste = heat )
2) A mosfet gets hotter when it provides more Ampere compared to the same output but at a higher voltage with lower Ampere

[zanzabar]

You are missing the point.

1) Lower driving voltage = mosfets operate at sub-optimal efficiency ( hint: worse efficiency = not as clean output, and more power gone to waste = heat )
2) A mosfet gets hotter when it provides more Ampere compared to the same output but at a higher voltage with lower Ampere

isnt that why they should have an 8+4 or 8+8 connector on the board. especially ones that are intended to push chips that are over 160W stock with turbo.

[BenchZowner]

Nope, it's ot required, unless the PSU manufacturer gets cheap and puts low quality connectors on their PSUs like SuperFlower did.
That voltage drop is ridiculous.

Haven't seen any decent and pricey PSU suffer such a terrible drop even during hot room tests

[Revv23]

You are missing the point.

1) Lower driving voltage = mosfets operate at sub-optimal efficiency ( hint: worse efficiency = not as clean output, and more power gone to waste = heat )
2) A mosfet gets hotter when it provides more Ampere compared to the same output but at a higher voltage with lower Ampere

Hey BZ, can you tell me where you got this info? This is the first time I've ever heard anything like this. By this logic I should go to Europe and run on 220 to get a cooler running PSU.

Edit - just realized I'm being somewhat combative, not meaning to have much respect for you, I just have never heard this. Certainly dirty power (droop, ripple,etc) can cause inneficiency... But major increase in temp (to the point of VRM throttling) because of 12v rail being low? (But still within spec)

[BenchZowner]

Even the first sentence you wrote is correct.

220V will net your PSU BETTER EFFICIENCY ( which also includes less heat output ).
If you want to look further into such things you should start reading something like an electrical engineering 101 book.

[zanzabar]

Hey BZ, can you tell me where you got this info? This is the first time I've ever heard anything like this. By this logic I should go to Europe and run on 220 to get a cooler running PSU.

Edit - just realized I'm being somewhat combative, not meaning to have much respect for you, I just have never heard this. Certainly dirty power (droop, ripple,etc) can cause inneficiency... But major increase in temp (to the point of VRM throttling) because of 12v rail being low? (But still within spec)

more input amps means more heat, if you look at the efficiency curves on a PSU they always have one for for 110-120 and one for 220-230 like this
*

[Revv23]

I feel like we are talking about different things here. I am asking how an in spec PSU is causing the VRM to throttle. Maybe I will pick up the EE book so I can find the section about tolorances

[BenchZowner]

Actually they aren't throttling.

Throttling would be dropping the output and the logic circuit downclocking the CPU.

They are simply "overheating", in quotes because they aren't really overheating, FETs are rated at 150C++ anyway and and under 125C which is the crappiest spec of FETs I've ever seen on a mobo from a major brand ( Asus, Gigabyte, ASRock, MSI, eVGA, etc ) is far from "problematic".

You may not want more heat in your case, but having mosfets running at 100C for example is far from creating any sort of issues.

Just like every single chip/circuit out there, FETs have their own optimal input and operating specifications, going outside those thresholds the efficiency goes down and as efficiency goes down heat output gets higher.
I can't seem to find a way to explain it in easier and clearer layman's terms.

[zanzabar]

Actually they aren't throttling.

Throttling would be dropping the output and the logic circuit downclocking the CPU.

They are simply "overheating", in quotes because they aren't really overheating, FETs are rated at 150C++ anyway and and under 125C which is the crappiest spec of FETs I've ever seen on a mobo from a major brand ( Asus, Gigabyte, ASRock, MSI, eVGA, etc ) is far from "problematic".

You may not want more heat in your case, but having mosfets running at 100C for example is far from creating any sort of issues.

Just like every single chip/circuit out there, FETs have their own optimal input and operating specifications, going outside those thresholds the efficiency goes down and as efficiency goes down heat output gets higher.
I can't seem to find a way to explain it in easier and clearer layman's terms.

they were throttling since the boards are exceeding their temp rating. the temps are not from the parts them selves but from the pcb close to it. if you read 120c+ from the board it is likely 20-50c over that on the part with those. that is why boards will throttle a bit when the vrm goes over 100-120 on the probe.

we also are going to have parts that can draw 40-60% more power so this could be a huge platform problem.

[chatch15117]

Even the first sentence you wrote is correct.

220V will net your PSU BETTER EFFICIENCY ( which also includes less heat output ).
If you want to look further into such things you should start reading something like an electrical engineering 101 book.

Lol i logged in the first time in like 5 years to say LOLOLOLOLOLOLOL

You said it well... EE 101

Rds(on) of mosfet generate heat

If your CPU need 300 watt

And you give it 11.4v instead of 12.2v(Stepping down to vcore)

It will draw more amps at 11.4v to reach 300 watt

Heat is Amps * Amps * resistance

Yes, AMPS SQUARED

Every millivolt matter

Regarts