Go with an ATX-compatible PSU instead of the Carnetix. I recommend the DSATX or one of the more powerful Opus models.
I have been trying to find the right parts for my carpc. I am new to building computers so I want to make sure i am buying the right parts and that they will work together. I want to run Music/Video(DVD)/GPS/Internet
GIGABYTE GA-945GCM-S2C LGA 775 Intel 945GC Micro ATX Intel
Intel Pentium E2200 Allendale 2.2GHz 1MB L2 Cache LGA 775 65W Dual-Core Processor
Carnetix CNX-P2140 185W Dual Output Intelligent DC-DC Regulator
The BU-353 GPS Receiver
havent decided on an exernal hard drive yet.. and not sure what to get for bluetooth for my Treo.
Thoughts? any feedback would be muchly appreciated
power you may also have to buy a high-power (more expensive) power supply to feed it.
many of us MP3car members use the Intel "little valley" mini-ITX motherboards. the 2 newest models (the D201GLY2 and D201GLY2A) have built in Core2-based Celeron processors that can handle all basic carPC programs (including everything you listed). they only cost ~$75 (since the processor is built-in to the motherboard, that price covers both items). the boards are smaller than micro-ATX and they only draw ~27watts, which will allow you to save even more money on a power supply.
carnetix models like the P2140 are meant to supply power to PCs that only require a single input voltage (like laptops or any other PC that uses a "power brick"). as darque mentioned you will need an ATX-style power supply. if you get a low power system like the little valley then you can buy a cheaper PSU like the M2-ATX.
iGuidance and it works great.
windows (XP at least) will not natively boot from an external HDD. it is possible to do it, but it's really not an ideal setup. for power and space saving reasons I would recommend you go with a 2.5" laptop HDD.
whatever you decide to do, good luck with your future carPC