is a 90 W DC-DC PSU more powerful than a 90 W AC-DC with a inverter?

bizardo · 10-19-2002, 08:21 PM

i have tried a 90 W AC-DC PSU with a 150 W inverter on my shuttle FV25 mobo with a VIA c3 700 mhz CPU, 256 MB RAM. But it will not boot... the cpu fan starts,, but nothing more,,nothing on the LCD screem the pc-speaker will not make any noise...

but if i use a 250 W PSU at home,, it will boot.. and get picture on the LCD.. i also have tried the 90 W PSU at home,not in the car, but does not work.. so i wonder,,, someone have used the MPBS1 12V DC-DC Power Supply on a FV24 and booted fine... WHY NOT ME?? i have also tried a 145 W AC-DC PSU.. still won't boot into bios, or display any on the LCD... i will try another CPU tomorrow a P3 6XX mhz.. or a celeron...

what shall i do? i need help quick,., i have not testet my ny 5,6" LCD monitor need to boot up an test it in the car

MR. Jan Erik Vangen
From Norway

CrazyLittle · 10-20-2002, 02:54 AM

Well, the bottom line is that a 90w PSU is 90w regardless of whether it's in the car or not. Does everything work when you plug in mains power (like an extension cord from your garage?) Cause if so, then the problem is with your invertor. I'm betting that your 150w invertor isn't actually 150w continuous, and is really rated more around 75w continuous, 150w PEAK... I'm betting you've already destroyed your invertor.

bizardo · 10-20-2002, 06:01 AM

i have a old pentium 300 with 32 of ram in my car now,, it works fine with 145 W AC-DC PSU.... so i think the inverter is working fine... but it's the new mobo that's not working in the car

well acctually not tested in my car, but with the same PSU in my bedroom... and will not boot... it boots fine with a 250 W... but why does i need so much power?
is there somthing wrong whit the mobo? shall i turn off USB, FIREwire etc.. in the bios

chuckyg · 10-30-2002, 03:00 PM

Quote:

Originally posted by bizardo
i have a old pentium 300 with 32 of ram in my car now,, it works fine with 145 W AC-DC PSU.... so i think the inverter is working fine... but it's the new mobo that's not working in the car
well acctually not tested in my car, but with the same PSU in my bedroom... and will not boot... it boots fine with a 250 W... but why does i need so much power?
is there somthing wrong whit the mobo? shall i turn off USB, FIREwire etc.. in the bios

one of the sites I was reading, someone mentioned they underclocked their CPU to conserver power.. if you're CPU is drawing more power than it used to, that would help cut the amount of power needed..

MP3DUB · 10-30-2002, 07:23 PM

A C3 draws on the order of like 5W, so it shouldnt be the processor.

ricko73 · 11-03-2002, 09:08 AM

I'm using a C3-800 (EPIA board) with a 145W ps and it works great. I'm moving towards the DC-DC deal though as soon as I decide which one I want. The one from Casetronics (in the thread by Telek) will run me about $70 to get what I need. There is another that I've looked at, which a friend is using in his setup for $120. Space will be the deciding factor on this one.

The one I've been looking at ($120 each) works from 9-16Vin, draws 20A max and has the following output

+5V@10A
+12@ 5A
-5@0.3A
-12@0.8A
+3.3@5A
+5VSB@1A

OA dimensions are
10cm x 20 cm x 4cm enclosed with a fan. Operating range 0-40C

http://www.pcpowercooling.com/produc...line_12Vps.htm

zootjeff · 11-03-2002, 01:09 PM

Quote:

Originally posted by ricko73
Operating range 0-40C

Is is really cold where you live?

ricko73 · 11-03-2002, 10:47 PM

Yes. It was 20degrees F last night.

Looking at the Opus specs that might be the best option so far, BUT I have a feeling that it is probably not exactly cheap.

I know my lcd isn't going to work well that cold anyway.