Connecting Carnetix P2140 to Intel Motherboard DG45FC

JonnieBlaze · 11-13-2008, 03:12 PM

Hey everyone,

I guess I'm a little confused as to how exactly to connect the Carnetix P2140 to my Intel motherboard DG45FC. I originally planned to use my laptop as my Carcomputer...hence the Carnetix...but since then I've changed my mind and would like to use a smaller mini itx style computer. I dont have any parts yet (mobo, cpu, hdd, etc) but I do have the Carnetix and I'm trying to figure out what all I need to purchase to build the computer.

My main question is, do I need some sort of 24 pin pigtail and 4 pin pigtail to connect to the motherboard then splice the Carnetix wires into those? Or do I need some sort of other PSU that plugs into the 24 pin connector and 4 pin connector on the motherboard, then the Carnetix plugs into that?

Where do I find out what voltage the motherboard needs from the main rail on the Carnetix? I can't find this out in any of the documentation from Intel.

Lastly, the ACPI wires from the Carnetix...these go to the 'power button' on the motherboard correct? And the 'power button' on the motherboard is really just two pins that you jump together to start the computer?

I searched around here and google and Carnetix website/manuals to help me understand this but I didn't find anything that definitely answered my questions. If you know of a FAQ or thread where I can find answers...feel free to direct me there.

Thanks!

pcpete · 11-13-2008, 03:21 PM

You need an additional psu unit, I use a 120W pico psu with my 2140 , feeding a microatx mb with an AMD BE2350 CPU, over one year no problems.

Bugbyte · 11-13-2008, 05:36 PM

You need an ATX power supply. The 2140 is a regulator only. That means it will provide smooth, regulated power and the auto on/off signal. You'll need an additional power supply for mini itx motherboard. If you keep your power requirements low, a Morex 80W power converter will work for you. They run around $30 at logic supply.

Alternatively, you can sell the 2140 and buy an intelligent ATX power supply such as the M2-ATX which combines the regulation, auto start/shutdown, and ATX supply in a single device.

JonnieBlaze · 11-14-2008, 02:27 PM

Well I'm not sure I want to sell the Carnetix because it can power my screen and my USB hub separately from everything else. So I think I'll keep that and just connect it to a simple DC-DC PSU. That way I still have startup/shutdown control even though I'm using a simple(cheaper?) PSU.

Now, I've been through the FAQ and went to several of the links to help me calculate what kind of wattage I'm going to need out of my PSU, and the only link I found that works in my situation told me I needed a PSU of 238 watts!? This doesn't seem right. I saw a thread a few weeks ago where someone was explaining how to add everything up on your own so you don't need the calculator but I couldn't find it in my search. Anyone know where I can find this information? Or can someone give me a jump start on how to add these up?

Here is what I'm planning:

Mobo: Intel DG45FC -- __watts on __rail
CPU: E7300 -- 65watts on 12v rail?
DVD/CD drive: Panasonic slot -- 4.5watts on __rail
Two SATA 5400 HDDs -- 2.1watts on 5v rail each -- 4.2watts on 5V rail
1 stick DD2 2GB RAM (maybe 2 in the future) -- how to determine this?
1 or 2 small fans - 1.6watts on 12v rail each? -- 3.2watts on 12v rail
USB devices:

BT - .5watts on 5v rail

WIFI - .5watts on 5v rail

wireless keyboard - .5watts on 5v rail

wireless controller - .5watts on 5v rail

Add 2 or 3 items here for good measure. - 1.5watts on 5v rail

Totals (still need to add the ones I'm missing above):
12v rail = 68.2 watts
5v rail = 7.2watts

These things should not effect what I need in a PSU right?...

10.4 inch screen powered by Carnetix
USB Hub powered by Carnetix
GPS from hub
USB Soundcard from hub

How is this looking so far?

Bugbyte · 11-14-2008, 08:09 PM

http://www.mp3car.com/vbulletin/advf...iew&advfaqid=6

Quote:

These things should not effect what I need in a PSU right?...

10.4 inch screen powered by Carnetix
USB Hub powered by Carnetix
GPS from hub
USB Soundcard from hub

Right, although if you choose to connect those devices to the carnetix, you need to account for the draw on the carnetix.

JonnieBlaze · 11-14-2008, 10:53 PM

Alright. So first and formost I need to narrow down my options by just looking at the CPU and the 12v rail. The CPU is 65w.

I found the picoPSU 120 and really like it because of its size and the fact that it plugs right into the 24pin connector. Also, it is a simple PSU so it required some sort of regulator inline before the PSU (such as the carnetix or a 'power brick' that can be purchased with the PSU). On the 12v rail is has 84watts max (12v X 7A). However, here is the problem. Input wise the picoPSU requires 12v regulated with a minimum of 2a and maximum of 10a. The Carnetix outputs 11a at 12v. That exceeds the maximum accepted amperage of the picoPSU by 1a. I have no experience, but looking at the numbers this setup will not work although the author of the second post in this thread says that's exactly what he is doing and it has worked for over a year.

Can anyone else confirm or deny this works?

pcpete · 11-15-2008, 01:53 AM

Been running this combo for one year no problems, also powering xenarc 7" screen + ****load of other stuff eg.. usb wifi, firewire powered maudio 410 soundcard , elmscan obd, bluetooth, logitech wireless mini dinovo, shuttle contour controller,slot load usb powered dvd drive, 2.5" 5400rpm hd, 1 stick 1gb ram.

My MB is asus microatx with AMD 780G chipset, my CPU is AMD BE2350 45W.

Rock solid, love being able to monitor my carnetix and change parameters on the fly.

I couldn't be happier with either picopsu 120w or carnetix 2140.

JonnieBlaze · 11-15-2008, 11:44 AM

The picoPSU only has one SATA power connector. That means I can only use either one sata harddrive or one sata cd/dvd drive. Can I use an adapter on those other power plugs on the PSU to convert them to SATA power connectors or is that going to mess something up?

Also, there is the 4-pin power connector on the motherboard that a PSU usually plugs into. With the picoPSU, there is nothing to plug into that 4-pin connector. What do I do there? I dont even know what the 4-pin connector is for...but I've build many desktop computers and the PSU always plugs into the 24pin and the 4pin connectors on the motherboard.

pcpete · 11-15-2008, 12:29 PM

You can split power connectors, as long as you don't overload your rails.

I'm using one of these for the 4 pin connector

http://www.canadacomputers.com/index...cid=CA.784.429

Bugbyte · 11-16-2008, 03:11 PM

Quote: Originally Posted by JonnieBlaze

Input wise the picoPSU requires 12v regulated with a minimum of 2a and maximum of 10a. The Carnetix outputs 11a at 12v. That exceeds the maximum accepted amperage of the picoPSU by 1a. I have no experience, but looking at the numbers this setup will not work although the author of the second post in this thread says that's exactly what he is doing and it has worked for over a year.

Can anyone else confirm or deny this works?

This is a very common misconception. The Carnetix has the ABILITY to SUPPLY 11 amps, if the load calls for it. Since your Pico PSU won't call for it because it will burn out at 10 amps (or shut off or whatever), the Carnetix is actually perfect for supplying it.

Electrical circuits either draw X amount of amps or supply X amount of amps. If there is no draw for it, they don't supply it. This is different than voltage, which is a constant output. If it says 12 volts is coming out of the device and your device can only handle 5 volts, you're going to have trouble.

So: Match voltages but you don't have to match amperages except to be sure that you won't draw more than the device supplies.

Voltage is like water pressure in a hose. Amperage is like the volume of water that gets delivered within a certain period of time. You can have very high pressure but the speed you can fill a 5 gallon bucket depends on the type of nozzle on the hose. Same with electricity - high voltage is 'high pressure' but amperage (the volume of the electricity delivered) can vary.

User Name		Remember Me?
Password