I was re-reading the last message of Marcelo Aguiar over his built, the Cintia
Over how he managed to have it usable, to then have to discard it because his new Laptop only had a DVI output, and with DVI the Cintia was unusable.
Now, this is not really a surprise - DVI are digital signals, which means that they are not required to have a "nice" waveform, and can pick up as much noise they want, as long as the logic levels are respected.
Also, we should remember the detail that the "ideal" digital signal - square - is supposed to have an infinite spectrum (composed by "spikes" at the harmonic frequencies of the signal's clock, in the envelope of the Fourier's transformed of a Dirac delta's... agh, whatever)
, which is the reason they can't be had in reality.
So, that DVI can stand in the way of using a DIY-q... it is almost natural.
At the time, it saddened me a little, but had no more to offer.
Anyway, ever since then, I came across the USB-to-VGA adapters and, I think these may help, in these cases.
I have two DisplayLink USB 2.0 to VGA adapters, and I use one of them as the VGA source for one of my builds.
USB 3.0 should work similarly, however there are many cheap adapters of that kind ( starting from some 15$) and, in my experience, they are unusable if you do not have a USB 3.0 port. I do not have any USB 3.0 port - my PC is that old.
Even though they advertise a USB2.0 capability, they simply have not enough hardware to make do with the less bandwidth allowed by USB 2.0 ( which is the reason why the USB 2.0 only adapters tend to cost quite a bit more... essentially, they are a compact video card reconstructing a VGA signal from a MPeg - or some lossless equivalent - stream made almost exclusively by B - difference - frames, whereas the 3.0 can do with a lot more A - integral - frames and need less intelligence in the adapter)
Anyway, stop digressing and back to the chop...
As I said, I have a couple of these buggers - a lucky acquisition in ebay, used but, hardly ever, judging by the condition of the cases - and I have take a look a bit at how they perform.
No, they are not a good idea, to watch movies on.
It can be done, but...
Graphic board -> Image -> Encoding -> send images by usb -> reconstruct the raster from the stream -> reading the raster as VGA
It will add some latency (negligible, in most cases... and I am using computer 8 and 12 years old) and it will dig into your CPU, as most - if not all of this - will be done in software, on the PC side.
(Again, it digs a lot, for a movie seen at 1440x900, on my 8 years old AMD double core... probably, it would be a far less troubling quota of resources, on a more capable machine)
Movies can still be watched, but I'd say, gaming through these things is definitely a bad idea (the more of an image changes, the more data has to be encoded and shipped, the more latency is added - and some of the latency is simply due to the data having to go through the USB at its maximum rate... ).
But drawing? drawing is a completely different matter.
Most of the time, it is about small changes (in my case, single lines - I am not a colours lover, to be honest)
Losing a 10th of second opening a menu is not going to feel particularly sluggish (more so if you got used to Lazy Nezumi at, say, 10 t0 20 steps of moving average)
, and chances are you'll see even less than that.
So, if your build is well behaved in VGA and goes bonkers with DVI - HDMI, my suggestion is - before scrapping it - to try one such adapter...
Note: there are some USB 3.0 adapters that also expose a USB 2.0 ancillary input...
Marcelo's build had all the size to put one such adapter inside it, hook up the Intuos to the USB 2, eventually using a 12-v to 5v to feed some more juice in the system , and his build would have needed only the USB and power cables... which would have been not that bad either.