in car pc psu

ok so i know this dumb questin has been asked a trillion times before. where can i get one or make one. making one is not such a problem for me but i am not sure on the control process that goes on between the pc and the psu during start up
many thanks
Simon

As You described, this is ATX type PSU. For ATX MoBo need a small additional standby 5V and when the start pins momentarily closed, the MoBo give continous GND to PWRON pin of PSU.
I mean, in-car application no need the ATX-function. (no wake-up from modem or LAN,etc.)

u mean the signaling between the mobo and psu r for advanced features and so i just need to power it and hit the start button (with 5V available of course).

get a inverter for £25 plug it into the cigeret lighter and your off... 8)

haha ha very imaginative pity the man that made ur inverter did not say the same where would that leave u hehe also remember that the pc psu is like 80 % efficient and so will the inverter be more or less the same so 0.8*0.8 = 0.64 thats 64 % efficient very nice ! what about the extra space. realy i think i have solved my problem i just need to undeertsand the signaling between the mobo and psu i know what was said above but am still a bit unsure because i read a project for a complicated in car psu that had a pic to do the power good ecc signals

The PWRgood signal only a delayed (cca.0.3sec, if more = not critical) +5V for releasing the MoBo reset. Most PSU have a delay cct with capacitor, and when the cap decreased, the PC only started with manual reset.