only issue I'd have with that build, troll, is the video card is just something else to fall out.
at the same time, I don't know any on-board that can handle more than 2 screens.
What's on these 4 kiosk screens, could two slim/small form factor PCs operate two screens each?
depending on what's being use, a system-on-chip very mini computer (like Raspberry Pi, or one of the similar, slightly beefer versions) might work well...no parts to fall out. although at one per kiosk screen
In theory, ivy bridge cpu's can handle 3 concurrent video outputs.
But, I don't know if there are any small motherboards that will support that.
Most of the time, the outputs are a mix of dvi, vga, hdmi to allow a selection of different monitor attachments.
If the monitors are all 3 vga, then I imagine that adapters can be used to handle the attachments.
If no suitable 3 output motherboard can be found, then it is easy enough to use a low profile graphics card.
As to transportability:
using a SSD would eliminate any hard drive mechanical failures.
Locking sata cables
backplate mount for the cpu cooler.
graphics cards are screw attached at one end, with a locking latch on the other. So, there should be no worries there.
What is the budget, and what does the pc need to do?
Are there any other peripherals required?
Are you trying to get 1 computer to do different things on each monitor are are you looking to get 1 computer hooked up to 3 monitors to show the same screen? A video splitter cable will do the 3 same monitor display.
You may run 1 monitor off the mobo d-sub analog, and one monitor off the HDMI digital. Install an inexpensive low-profile discreet card for monitor #3 (and #4 & #5 if you spend $70-$80 on an 'Eyefinity' discreet, and use an active displayport).
For another $200 or so you should be able to pull together an ITX case with power brick, SSD and RAMs ...
There are custom pc builders out there who will build one to your specs. If you are looking at a large number of units, I suggest you design and build a prototype first and evaluate it before comitting to a large number.
Why not use a laptop?
They are somewhat rugged, and will come with a couple of video outputs. Probably two, but not three.
Since your displays will be static, you could handle them using a usb to vga video adapter. They are not expensive.
Something like this: http://accellcables.com/products/computerCables/USBDVI/...
There's a lot of reasons why I don't want to use a laptop. A biggie is that when the kiosk receives power I want it to turn on, which laptops can't do. This is an industrial application and I want maximum reliability and simplicity.
The Matrox products are interesting but more of a hack.
I'm surprised this is so hard to find. The best option I've found so far is to use Mac Mini's, which seem to be built 1000x better than any other small PC's I've found, and install Windows on them.
The last time I built a decently performing small computer it came to around $900 and it was vastly inferior in almost every respect, except that it had 3 DVI outputs.
It seems that the PC universe is really lagging behind Macs in terms of quality. I hope I'm wrong, but no one seems to be able to produce a link showing a PC manufacturer that can prove otherwise. And with the price of Macs falling so much this is really going to be a problem for the Windows universe I think.
And I should mention that I'm not a Mac user.
And as far as your other point, using 2 computers to do the same task is twice the liability and complication. Price isn't the main factor for me (in fact its pretty much not a factor at all), durability, reliability and simplicity are the only things I'm worried about. Well, that and being small and having the ability to run 3 monitors.
sorry, Macs are no better than Dell or Lenovo in build quality. they really aren't.
the starting mac mini is basically a $500 i5 notebook with half the ram and no screen.
Well, there's nothing wrong with an i5 notebook as far as I'm concerned. That's plenty of processing power, and beats the heck out of an Atom type thing.
I thoroughly disagree about any small Dell or Lenovo being comparable. The Minis are much smaller and about twice as powerful, and I don't think any small Dells or Lenovos even have dual monitor outputs. Though of course a link to the contrary would be invited, I'd love for you to be right.