single or dual carpc quest

**gommer** · 09-16-2006, 12:05 PM

I'v searched this forum for dual computer setups, but unfortunately had no luck.

What I want to achieve is the following functionality:
3 screens, with the usual stuff minus video in the dash and 2 headrest screens for the backrow. The back screens are for video only and these screens would show the same source. The front would run GPS, radio or MP3 audio and OBDII apps, while video with seperate audio should be able to run at the same time for the back screens (through IR headphones). I can't imagine i'm the only one wanting this kind of thing.

Now for my quest, should I go for 1 beefy computer (P4 mobile maybe) or should I go for 2 seperate pc's (probably 2 VIA baords). I'd like to control all from the front screen. Putting a DVD in the front, this would then be read from the front PC and played / viewed on the back PC. Controls for start stop, pause would still be run on the front PC / TS.

Either way, i'll run into headaches, i'm sure. Getting the single PC to do independant sound and dual video out or getting the front PC to control the back PC with a dual setup (I think girder and a serial link should be able to do the trick). I've not looked at the price difference, but that's a smaller priority. I'm more worried about getting it to work and have smooth playback of audio and video at the same time. Having the possibility to have the backrow video on the dash screen when wanted, would be nice too, it's not essential. I have absolutely no idea with which setup this would be easiest.

Please tell me you're thoughts, links, idea's or anything that can help making my mind up.

**FC3S** · 09-16-2006, 12:10 PM

personally, i'd just use one computer, i've read that the via's can output to 2 screens without too much problems.. mind you, you may need 2 video cards, and the via's usually only have one pci slot, so the audio might be a harder issue since the pc would need dual sound cards to be able to output dual audio if you wanted that..

but i doubt u'd need a p4, since they're a waste of power anyway.., could use an older athlon, maybe 1.4-1.5ghz, with 2-3 pci slots on the mobo, and u'll be fine

for the rear screens, if they're going to show the same thing, just use a video splitter

and there are lots of programs out that control what goes on what screen, "Ultramon" is one, check it out, might work for what you want, so ur gps set to the front monitor, and ur video program set to monitors 2 and 3..

as to having the front play video as well, just change the config, set the screens to clone

**Killa200** · 09-16-2006, 12:14 PM

i'm trying to think of some ways you could do this running a dual head videa card. Technically it should work just fine. You could open up the dvd proggy on screen 2 (back set) and all your nav stuiff on screen 1 (front), but my biggest concern is getting them to remember that on reboots and shutdowns (not a problem, if it doesn't, just a pain moving it all before the drive again).

Sound wise wouldn't be hard. I've work with dual soundcards and most apps are good about letting you specify what sound card you want them playing from.

**turbocad6** · 09-16-2006, 01:53 PM

hey, i don't think i've seen any others doing something quite like you mention, but I am, I'm currently doing this in my install....

I'm using 2 lvds motherboards, & I have 4 pc screens, 1 main 12.1" in my center console, 1 8.4" in my overhead console, & 2 10.4"s in the rear of the front seats, for the back seat passengers... all of my screens are in portrait mode, but this isn't necissary for this design, although all screens need to be in the same orientation..

to do something like this can be pretty complicated, & controlling everything from the front is a must for me...

I have considered many ways of pulling this off, I've looked into many different options, & I can tell you that pretty much everything out there would be a comprimise & a headache to say the least... running 4 screens off 2 computers is easy, but having full control, & fully versitile was my main goal, & I wanted to do this while avoiding having a birds nest of wires & switches, & a bunch of different components hacked togeather...

I wanted to do this as clean as possible... this is not my first, second or third carpc, I have done quite a few through the years, & I wanted this one to be all out & 100% pro....

to make a long story short, I have actually had to develop my own lvds multiplexer... which is a 4x4 matrix, I can display any one of 4 different inputs to any one of the 4 different outputs(screens)... this is all controlled by a microcontroller, I have a vfd display in my overhead console connected to this, & it displays system status of each display & which input it is running at the time..., I can also override to camera input at any time..

when my car starts, everything boots up... my main 12.1 display defaults to pc1 main, my 8.4 overhead defaults to the second output of pc1 as an extended desktop... my 2 rear screens default to pc2 main display..... when I put the car in reverse the 8.4 overhead switches to my camera's multiplexer for rear view, parking asist, & then returns to whatever was on that display when reverse is disengaged...

I have 4 small buttons at the vfd that are for each screen, so I can switch any screen at any time to whatever input I want... this also switches the touchscreen for whatever display, to be with whatever is displayed... I can't tell you how complicated this is, & I hate to think about how much it has cost me to develop this for myself, I am working with my own private engineer to develop this, but it is sure to be one of the most radical carpc installs yet, & it will really give me everything I could ever want from my install....

my whole system is built on it's own internal network, I have a kr1 mobile router, & all of my media is on a terabite of storage in a networked enclosure, so any pc can access any media or internet without depending on the other pc..., my car is also it's own hotspot & remote media server...

what were talking about here is radical to say the least, & for you to try & do this with stuff that is currently readily available would be very difficult & sloppy, but of course if your determined & spend enough time, money & effort, you can do a multi pc multi screen setup, I wasn't looking to make any comprimises though, & I am pleased with what I have developed...

my engineer said I was crazy for wanting to do this much r&d for a one off piece, & suggested that I try to find a market for this, to try & recoupe some of my expenses, my answer to him was, I don't think there are many others who are crazy enough to go to these extremes with there car, but when I'm done, I may make this available to others... expect it to be expensive, but custom limited production hand made electronics such as this is expected to be expensive I guess....

check out my install if you have a chance, & if this interests you let me know. there is one main board that has one cable to each screen, & one cable to each input & all switching & control is done internally, so this is as neat & compact as possible... there is also a usb multiplexer being developed for the auto switching of the touchscreens & mice, keyboards, etc..

definatley not for the faint hearted, but if you want a totally awsome one of a kind install, this may be an option for you, if you have the patience too, as this is still a month or 2 from finalized, but at that point I can give details of what this would cost & how available this may be to others...

if your not nuts, then just disregard this post

these pictures are just from the control portion of this

**FC3S** · 09-17-2006, 12:59 AM

rofl, turbo, ur design is sick

but a single computer with either dual vid cards, or dual-out vid card would be easier

basically he only wants 3 screens, 2 displaying the same image, so in essence only 2 screens..

so, dual out/dual vid cards is by far easier than what you want, he didnt even mention if the rear screens would have any input functions to the computer

**Jahntassa** · 09-17-2006, 01:37 AM

A dual-output card by nVidia should do the trick great. From what I can see on their newest FORCEWare drivers, the desktop management software does a great job at directing certain programs to certain monitors.

**FC3S** · 09-17-2006, 01:46 AM

im pretty sure Ultramon can save what progs go to what screen

but hell, if the video cards drivers can do it, then ur set

**gommer** · 09-17-2006, 12:34 PM

Hey guys, thank you so much for the replies so far. I'll try to give some comments on the suggestions:

@ turbocad6: yeah, i've read your post through, I guess i'm completely

too then. But nevertheless, it's a bit over the top for me. I only need 2 sources for 3 screens and no (touch) control for the backseats. I was aware of your install before my post, but never realized you had a dual PC setup.

@ everyone else: seems you all would go for single PC, dual head video.
I've tried this with my desktop PC (ATI 9600XT), which doubled as HTPC. I tried to run a normal desktop while playing video on the TV. It technically worked, but was bad. Only the primary display had video acceleration and the second had none, could barely cope with normal office apps. And the video (TV) needed the acceleration to play smoothly, so it had to be primary display. Furthermore, switching between single desktop and dual mode with hydravision proved to be very unstable. I wonder if this would be better with dual videocards or nvidea (as opposed to ATI).

The ultramon app seems to be very interesting. Thanks for the hints.

I know there's plenty of dual screen threads on the forum, so i guess i'll have to check them out and try to find some stability reports. If anyone cares to comment here, please do so.