Low Power CPU

[Puppetmaster]

I am planning to build a Mini ITX car pc in the summer. I'm wondering what cpu to put in it.

Atom has crossed my mind, although in not sure if it will be powerful enough. In terms of spec it will be:

2 - 4 GB RAM
120GB SSD
Onboard Graphics
Windows 7 Pro
7" Touchscreen
Mini USB Wireless
USB GPS Recevier
USB Radio Receiver
Bluetooth (Maybe)

Don't need anything graphics wise, basic onboard is fine. It will basically be running some sort of software with everything integrated (likely centrafuse) that will control Music, Radio, Sat Nav etc.

Any suggestions? I was thinking maybe 1155 Mini ITX board with an i3-2100T or maybe a Pentium Dual Core.

 

[Puppetmaster]

Regarding the windows 7 Pro, I can get one from work so it saves me spending money on the OS.

How much power at relative load do you think the above pc would use? The psu's designed for car pc's come in either 150W or 250W I believe. I was probably going to go for the 250W just to be safe.

 

[Puppetmaster]

I am planning on powering the touchscreen from the PC psu, as it handles voltage fluctuations from the battery when starting the car, using electric windows etc. Also means its only on when ignition is on.

I need to find out what power that draws but i don't think it is very much. On an american car pc forum, they have an atom powered itx pc with the touchscreen as well running off the 150w i think so shouldn't be an issue

 

[Puppetmaster]

On further inspection the 800x480 res 7-8in touch screens generally used in these car PC systems only draw ~10W of power. So with an Ivy Bridge i3/pentium CPU, Mini-ITX board, 4GB RAM and the screen I don't see drawing much more than 100W total from a PSU, so a 150W PSU should be fine.

May I ask how you will be hooking up the sound, will it be a digital connection to the car's onboard sound or do you need to use an analogue connection? If it is analogue, would you consider using a discrete sound card for better sound quality?

The plan was to go from onboard using 3.5mm to RCA into a regular car amp and then from there into the 4 speakers. I was thinking about using 5.1 sound outputs, but on my pc atleast i only get sound from my front speakers when playing music.

I have seen someone that used front speakers + line out reconfigured as front speakers, using 3.5mm to rca into the amp that seemed to work well.

At first it will likely just be 4 speakers + 2 tweeters at the front. I guess I may add a sub at a later date, although not too sure where to put that.