Correction: PCIe 4.0 won't support up to 300 watts of slot power

Seriously Cap! (pun intended) The storage they were referring to, no they don't. Capacitors are not batteries.
They're "not batteries" to the extent where they don't generate electricity. But they absolutely do "store" electricity, especially in power supply, and voltage regulator circuits.

The only thing that prevents them from storing electricity is the load from the connected circuitry. You really could take one of those big electrolytics in a PSU, charge it from the supply line, walk around the block with it, come back, and read very close to the same voltage you put into it.

The "filtering", and the "stabilizing", are both predicated on the storage function of the caps.

Now, once upon a time, in the dark ages before digital synthesis being used to tune to a given frequency, they used variable capacitors to tune radios and TVs.

Here's a variable tuner capacitor, from days of yore:

Variable_Capacitor.jpg


The capacity increases as the leaves mesh more.

So, a cap in league with a resistor or some form of inductor (choke coil), and you can tune a circuit to a given frequency or "band pass".

A third common function of capacitors in electronics is to block DC. A capacitor will pass AC as though it wasn't there (*), but will completely block DC from moving through it. These are use between stages of an amplifier, where you want the AC signal to pass to the next stage, but you want to maintain the supply voltage within the stage the signal is leaving. If you allowed the DC to pass between stages, all you'd accomplish is making the DC voltage higher at the transistor collector of the following stage.

If you think about it, the reason they call them capacitors, is because they have "capacity", which in this case, is a synonym for "storage capability". In that sense, they are "batteries" The storage and discharge simply isn't prolonged as would be the case with a lead acid type of storage battery.

(*) The reason for that is the AC wave charges one side of the cap, and then it releases it when the voltage shifts polarity. Then, the other side of the cap charges, and the cycle repeats.

So, here's a quote from Wiki: "The large capacitance of electrolytic capacitors makes them particularly suitable for passing or bypassing low-frequency signals up to some mega-hertz and for storing large amounts of energy. They are widely used for decoupling or noise filtering in power supplies and DC link circuits for variable-frequency drives, for coupling signals between amplifier stages, and storing energy as in a flashlamp".

And the attendant link: https://en.wikipedia.org/wiki/Electrolytic_capacitor
 
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Then what about a liquid cooled MOTHERBOARD?

Attach the tile to a bunch of coolant tubes that are integrated into the board...I can see it.

They're "not batteries" to the extent where they don't generate electricity. But they absolutely do "store" electricity, especially in power supply, and voltage regulator circuits.

There are a lot of Cranky skeptics out there, but he speaks the truth.

Unplug your PC, switch the power supply button to OFF, then stick your finger inside it and feel the capacitor.

I guarantee you will be shocked by how much energy a capacitor can retain.

(Edit for reasons of liability: Do not actually do this as it will probably kill you.)
 
Then what about a liquid cooled MOTHERBOARD?
What about it? They've been soaking entire Cray computers in oil baths for more than a decade. Would you want to "upgrade a video card" under those conditions. I guessing it would take most of the fun out of it.
 
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Well Cliff, you got 2 out of 3. Capacitors DO store electricity, and that's the mechanism by which they regulate, filter, and stabilize.

In a PSU, the capacitors are "charged" up to the average voltage of the power line they're on. In the case of the rectified output of the transformer, that voltage is nothing but a string of sine waves. In the case of a "full wave rectifier", the negative portion of the AC wave is turned, "upside down" to positive. So, the cap "inhales" that choppy power, and releases it when the voltage drops, to smooth out the waveform toward flat line DC. What is left after that process, you'll hear referred to "AC line ripple".

The residual ripple in the wave is kind of what you hear in an audio amp turned up, in the absence of a signal. Resistance causes the "hiss" you hear, and the AC ripple causes hum. (Some hum is also inducted from surrounding electrical fields, "EMI" if you will).

So, even rectified and filtered power from the PSU/line, isn't pure enough, (still too much ripple) for serious CPU-ing, which causes the need for the VRM, (voltage regulator module), which surrounds and feeds the CPU. The MOSFET acts like a spigot, responding to the rise and fall in voltage, by limiting the peaks, and "opening up" to allow more pass through when the voltage in the supply drops. The caps do store electricity, but they don't "supply it", the PSU takes care of that but those caps in the VRM provide additional filtering, flattening the DC voltage to almost a dead straight line. So, in short MOSFET = voltage control, Caps = final filtering out of any residual AC ripple

The classic use of large capacitors is in audio amplifiers. Since music is basically one big choppy AC wave, the peaks would draw down the PSU voltage causing the amp to distort or "clip". The caps release their stored capacity top prevent the supply voltage from dropping. After the signal ebbs, the caps recharge and the cycle begins again.

Another classic use of capacitors as storage devices, is with hard to start electric motors, such as those in air and A/C compressors, Without the cap in the AC line, those types of motors would never start, they'd just sit there and blow fuses, due to the stall condition creating massive inrush current. Don't forget, a stalled electric motor can draw virtually unlimited amount of power, up to the point where it destroys itself.


Who writes this nonsense for you? It's like the prosaic "fractured fairy tales of electronics 101". A "Metal Oxide Semiconductor Field Effect Transistor" certainly does not "store" electricity. And this may be a semantic point but capacitors "store and release electricity", they don't "supply it". Which is why the "S" in "PSU" stands for "supply".

additional capacitors on a motherboard would power up a pci express lane in some type of gateway connection. and the same way mosfets would amplify the energy passed. where did you guys go to school. the school of the retarded. how else would a mobo supply energy from a psu to a component on a motherboard. you think it would just pull it from the 24pin power connector without any additional components such as capacitors and mosfets on the board.
 
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Where the hell did you read that from? Gateway, seriously a gateway! It's power that has no need for conversion. Passive is fine, which is exactly what the GPU connection from the PSU does. And no Capacitors and Mosfets don't store energy, they regulate and stabilize.

before a component get energy it goes to the mobo then to caps and mosfets then to component. you think you can just place a cpu socket on a mobo with a power connector without any caps to store and release energy and mosfets to amplify and clean up the energy. what kinda clowns are you guys. every component on a board has goes through a phase power regulation like a step down transformer on power lines so that components get the correct wattage and voltage and amperage to operate on a board. damn guys what kind a school have you been too
 
additional capacitors on a motherboard would power up a pci express lane in some type of gateway connection. and the same way mosfets would amplify the energy passed. where did you guys go to school. the school of the retarded. how else would a mobo supply energy from a psu to a component on a motherboard. you think it would just pull it from the 24pin power connector without any additional components on the board.

Please stop telling me I'm "retarded". You haven't formed a coherent thought through this entire thread, and all we are treated to, is some bizarre bullsh!t about "magic gateways", and "MOSFETs, amplifying power"

Read my lips, "the only power present on the board comes from the PSU alone".

No other component on the boards produces power. Everything else, loses power through the production of heat. The other components modify the power, condition it, and direct it to where it's needed.

FWIW, my father was in the army signal core during WW2. After which, he committed to being an electronics technician.

The point being, growing up in that environment, made it possible for me to know more by the age of ten, than you imagine you do now.

And as for, "phase regulation", that's why there are different voltage taps coming from the PSU. The PSU delivers power as needed to the circuit.

If the graphics card needed additional filtering or storage capacitors, They'd be on that board already.

And that kidz, is why the put the power tap on top of the graphics card itself, because the current flow is so high. It makes no sense to direct that power through the PC board's traces, which would likely burn them out. Regardless of how many dumb a** parts you try and slap on the board.

The PSU wires are thick, the PC board traces are thin. Thicker wires are able to carry more power. Got it?
 
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Woo inaccurate journalism!

I knew the last thing didn't make sense; how could it? At least, not yet..
 
@captaincranky I don't know about you, but I've read enough from this guy. Please don't respond and provoke another crazy response from him.
No problem, I'm done.
And the circuit he is adding to the motherboard would be a redundant circuit over that which is in the PSU.
OK. the reason the plug is on top of graphics cards, is simply because the PCB traces won't handle the power the larger cards need. The heaviest draw I'm aware of being handled by a mobo alone, is the 60 watts of the Nvidia GTX-750ti. And keep in mind, the "extreme gaming / overclocked editions" of that very same GPU, DO have 12 volt plugs going to the top of them.

This article was a retraction of an overstated, and completely erroneous article, yet every fool in the building, thinks they know, "how it could be done". You can't convince me the most sensible and viable method isn't already is use, which is, separate power to the card.

Let's suppose we want to put 300 watts of power to a single PCI-E lane. It should be obvious that the PCB traces wouldn't handle that much power. So, in order to enable that much draw at the socket, you'd have to widen those traces, and when you did, the damned socket would have to be likely near twice as long. So, an entirely new PCI-E standard, which would sh!t all over universal PnP, would be "needed".

If a card needed further filtering, it would be done on the card.
Well, I did say something similar above. But the facts of the matter are, it's already done that way.

A GPU (which is where all that darned electricity goes), is nothing if not the "CPU", of a graphics card. As such, it needs all the voltage stability of its cousin on the motherboard. So, given that the speed of electricity, (which is damned near the speed of light), is becoming a factor in modern computer circuit design, in that it requires all components be closer together than they ever were in the past, for a multitude of reasons. It makes no sense to condition the power for any type of central processor, anywhere but dead next to it.

With that said, I'm sitting here with a lowly GT-710 in my hand, and seeing what appears to be a VRM circuit, just outside the heat sink. Look at one of your cards, You'll see a couple of cap cans right where I'm predicting they'll be.
 
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EDIT: I just thought I'd put this out there. I should have written into my post above.. Any "Repeater", would require a power source/ power supply of it's own, or it wouldn't repeat or amplify anything. This is in spite of how many capacitors and MOSFETs you might try and slap in the damned thing..
 
The could at leat leave the gpu power connector on a better place... when you get an slim case, the power cable can sometimes touch the side pannel/side window.... I used to have an Corsair 240 with an GTX 970, I had to guide the side pannel with both hands, and still the gpu power cable was pressed agains the side window...
If it was an AMD bigger card it wouldn't even fit.
 
The could at leat leave the gpu power connector on a better place... when you get an slim case, the power cable can sometimes touch the side pannel/side window.... I used to have an Corsair 240 with an GTX 970, I had to guide the side pannel with both hands, and still the gpu power cable was pressed agains the side window...
If it was an AMD bigger card it wouldn't even fit.
I let this slide earlier, now I'm awake. So, "aw poor baby".

First off, real men build in full tower cases which do indeed have the room to plug in the graphics connector.

But more importantly, that issue is more than likely caused by some dumb SOB, or summer intern, who simply doesn't have the presence of mind to notch the PCI connector, 1/4" deeper into the board when they drew the designs for it.

Universal PnP is a grand concept in the overall scheme of computer tech, but sometimes as they've said for eons, "the right hand doesn't know what the left hand doeth

Second, the imbeciles at the PSU factory, could just as well design a right angle connector for the video cards wiring as standard. Problem solved, and without doing something as silly as running 300 watts of power through a PCB. That's nigh on as stupid as putting pennies in your home's fuse box.
 
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