Boot Disk failure using snap-on 200W + ITPS on my VIA

**NTurkey** · 09-26-2004, 11:00 AM

I searched the forums, but I couldn't find my answer. Perhaps I didn't search well, but I'd love some help.

I just got my Carputer installed, and it's powering on correctly, but in the POST it's telling me that I have a boot disk failure. When I pull the PC from the car and run it inside the house with an ATX power supply, it works just fine.

Seems almost as if the hard drive isn't being powered correctly. It's not making it's spinning noise it normally does.

Has anybody had similar problems? I sent the store email regarding the issue, but I doubt I'll get a reply on Sunday.

Anybody have anything ideas to help?

**mindscream** · 09-26-2004, 11:04 AM

You might try, if you have a volt meter, see if the +12v and +5v rail off the PSU are actually putting out the correct voltage.

If not then there's a definite possibility that the PSU is bad.

It could also be that the pins inside the connector aren't connecting right. I know it may sound stupid, but have you checked to make sure that the molex plugs are not allowing the pins inside to slide back when you connect it?

There could also be a solder connection that has worked itself loose.

Just some suggestions

Mind Scream out

**pioneer** · 09-26-2004, 11:38 AM

Listen to see if you can actualy hear the hdd spin up.
iv heard that those snapon psu's can be a bit doggy and they dont actual regulate the 12v line its just 12v strate from the car.

**brooksware2000** · 09-26-2004, 12:39 PM

What size HDD are you using? If it is 3.5" drive then most likely it is not getting enough power to make it operate correctly. If you happen to have a laptop hdd lying around then I would try that and see if it works. You could also try starting your car and then powering the system without the ITPS in line to see if the voltage drop across the ITPS is causing your problem. Of course, like the other posts, you can use a voltmeter if one is available.

**gospeed.racer** · 09-26-2004, 01:02 PM

I have a pw70 and it will not power up a full size rom and a hard drive at the same time. Until I switched to a slimline rom, it would produce a boot failure. Sounds like you dont have enough power supply for what you are powering, especially if you have a lot of add ons, like video card, usb accessories, ect.

**NTurkey** · 09-30-2004, 03:34 AM

I finally figured it out.

I took mindscream's suggestion, and checked out the voltage off the PSU drive connector. The 12V (yellow lead) wasn't getting 12V. It was only ~9.2V -- apparently not enough to spin up the drive.

But ... here's the newbie thing ... I was trying this without the car running. It was in ignition, but not running. Once I turned the car on, all worked great. Is that silly, or what?

Thanks for the help, everybody.

**ptk** · 09-30-2004, 04:43 AM

Originally Posted by NTurkey

I finally figured it out.

I took mindscream's suggestion, and checked out the voltage off the PSU drive connector. The 12V (yellow lead) wasn't getting 12V. It was only ~9.2V -- apparently not enough to spin up the drive.

But ... here's the newbie thing ... I was trying this without the car running. It was in ignition, but not running. Once I turned the car on, all worked great. Is that silly, or what?

Thanks for the help, everybody.

it's the ITPS dropping the voltage.

**NTurkey** · 09-30-2004, 02:36 PM

Originally Posted by ptk

it's the ITPS dropping the voltage.

What would you suggest to "fix" this, other than having the car running when I power it up. Once it's spinning, it works just fine when the car is off (although I haven't tested it for very long).

**Rob Withey** · 09-30-2004, 02:41 PM

Originally Posted by NTurkey

What would you suggest to "fix" this, other than having the car running when I power it up. Once it's spinning, it works just fine when the car is off (although I haven't tested it for very long).

Throw away your ITPS - it's junk.
Buy a Carnetix regulator - much better by all accounts, doesn't suffer from the linear regulator dropout.

However, note that both the ITPS and Carnetix regulators are limited to 60W (unless you bypass the regulator on the ITPS). So much for your 200W power supply.

**Confused** · 09-30-2004, 03:12 PM

Originally Posted by Rob Withey

Throw away your ITPS - it's junk.
Buy a Carnetix regulator - much better by all accounts, doesn't suffer from the linear regulator dropout.

However, note that both the ITPS and Carnetix regulators are limited to 60W (unless you bypass the regulator on the ITPS). So much for your 200W power supply.

Exactly

The ITPS itself is bad enough, and when paired up with that "200W" power supply, which is terrible too, you get a really bad combination.

Get yourself a Carnetix, and you can use your current "200W" power supply, or get yourself an Opus

Garry