Making my own shutoff switch

**error_911** · 03-12-2005, 04:23 PM

Alright, I'm in the midst of putting together my car-puter and love the idea of having the PC boot and shutdown on its own alongside the ignition. Thing is, I don't feel like spending $200 on a PSU with that function. I've got the computer ready, with a standard ATX PSU, and then a 400W power inverter (easier for me since I need the extra sockets, and cheaper than getting a DC-to-DC PSU). Now, the inverter has a safety shutoff at 10.5V, but how would I go about making a relay switch to get the PC to shut down when the car turns off, and to turn on again when I start the engine? Thanks guys.

**WebDog** · 03-12-2005, 04:25 PM

well how many watts do you need? the M1-ATX is a start up / shutdown and PSU for like $70

**error_911** · 03-12-2005, 04:37 PM

I'll be needing about 200W - the PC will be a P3 1Ghz, 256mb ram, 10Gb hard drive (will be running most stuff off of external usb drive, with usb ports routed to front of car), dvd-rom, wireless nic, wireless mouse/kb, 7" LCD... thats about it.

That M1-ATX seems to be 90W, and no matter how good they are I'm still not convinced it'll give me enough juice.

**code-** · 03-12-2005, 04:40 PM

Yes they will...

**error_911** · 03-12-2005, 05:36 PM

Originally Posted by code-

Yes they will...

Dude, I know they're supposed to be good and all, but seriously - running that from a 90W PSU? I mean if it was a VIA EPIA mobo and cpu I'd agree, but its not. Just the processor and RAM will suck up two-thirds of that wattage.

Any reviews on the PSUs running anything more power-hungry? That would convince me a little more.

**WebDog** · 03-12-2005, 05:41 PM

Originally Posted by error_911

I'll be needing about 200W - the PC will be a P3 1Ghz, 256mb ram, 10Gb hard drive (will be running most stuff off of external usb drive, with usb ports routed to front of car), dvd-rom, wireless nic, wireless mouse/kb, 7" LCD... thats about it.

That M1-ATX seems to be 90W, and no matter how good they are I'm still not convinced it'll give me enough juice.

well im runing the M1-ATX with a M10000, 256mb ram, 60gb 2.5" hdd, 7" lcd, then i got on USB, Cell phone charger, GPS, WIFI, Keyboard, CD-ROM, AUDIO out, Bluetooth, toch screen. all going at once and i havent had a problmem with it.

How much juce the p3 suck up?

**SFiorito** · 03-12-2005, 05:55 PM

http://carpc.kyferez.com/Products/cu...arpcez2.4.html

**error_911** · 03-12-2005, 06:06 PM

WebDog: a 1Ghz P3 sucks up about 35-40W of juice. But you might be right, and i'm going to start looking around for some reviews.

SFiorito: that shutdown controller is $60, I might as well buy an Opus.

... which reminds me - where the hell do I buy an Opus ?