yes games are either ntsc or pal for it, but i never thought this would reflect back to the power supply itself! i mean as long as we provide enough capacitance and filtering, it should not dip much.
It necessarily reflects to the power supply, of course!
Indeed, if you've ever had the experience of a poor quality or failing adapter, you may've noticed this as the consumption of your PC/laptop/phone/widget varies with function. Or, I had one occasion I was running my laptop off this shitty inverter thing I made,
The output filter inductors and/or capacitors vibrate slightly when switching (it's a "modified sine" output), and more when under load. So the laptop's variable load is almost immediately (within 10ms or so) reflected in the sound of the inverter. It's audible, responding faster than Task Manager's CPU gauge does.
Indeed, a power converter is a lowpass filter of sorts; it might add some noise, too, but to the extent we can null that out or otherwise ignore it, its behavior is dominated by the energy storage components that make it up. So, input and output filters, and whatever the conversion mechanism is (usually a switched inductor, but sometimes capacitors are used, or a combination thereof).
An ideal power converter, I suppose you could say, stores no energy and transforms input to output (or vice versa) instantaneously. Converters have certainly improved along such a trajectory, over the years: going from low frequency switchers and huge inductors (low ripple fraction), to higher ripple fractions (peak current mode, resonant) and higher frequencies.
Note that ripple fraction basically says how much energy is stored, or how many cycles it takes to build up / release the full energy of that element. A ripple fraction of 30% means that about 30% of the energy is circulated each cycle, so takes about 1/x or 3 times that (3 cycles) to fully dis/charge that energy.
And doing that at higher frequencies, then, simply goes faster. Your regulator might be around this level. So, at 700kHz, that's a power bandwidth, so to speak, of ~230kHz. The input and output filters cut generally lower than this, but this would be the limiting case, if you for some reason needed fastest response from load to source.
Some converters intentionally store energy, for safe keeping (hold-up time), or because the source itself is intermittent (single phase AC). Note that 3-phase AC needs very little energy storage, because power is available continuously, and indeed many industrial converters only use modest filtering, to take advantage of this.
In any case, sooner or later, change in load must be reflected by change in draw from the source. Even a battery isolated system must be charged sooner or later, and the amount of charge equals (well, modestly exceeds, due to losses) the load consumption over that time.
This is even relevant for SIGINT purposes. The power consumption of a building or room can be monitored, and information can be leaked out as a result. (A battery-isolated design might be required to help mitigate such attacks, even if power is generally available at the location!)
Tim
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