Splash Screen, but no POST

[kopfjaeger]

Greetings Tekkies,

Your mission for today:

Hewlett Packard SS7 MoBo, power comes on, no main board error beeps, Hewlett Packard splash screen comes on, but after about 1 1/2 seconds fades to blank screen, no Power On Self Test (POST).

Thereafter, machine does not respond to Crtl-Alt-Del.

Upon rebooting, I have tried holding down the "F1" or "Del" keys, attempting to get into CMOS setup. Same thing as described above, takes place. Machine ignores keyboard commands. Have swapped out known-to-work keyboards without improvement.

Have tried booting with a startup disk in A drive. The floppy drive is ignored, but has power.

On a side note, I suspect the power switch is not original or is somehow improperly set.

Basis: the power switch connected to the button bar pins array consists of a standard reset switch and two LEDs, all feeding into a single-piece connector.

Even without touching the power button, upon plugging 115V AC power cord into the power supply, the machine automatically switches on. One of the LEDs lights up and stays lit (most likely the power LED). The other LED is known to work, but does not immediately switch on.

Clicking the power button generally has no effect on the power once the wall plug is jacked into the power supply -- yet this is not always true. I have managed to switch the machine off at least once using that switch.


Analysis Spock?

Thanks in advance,

KJ

[bailey]

symptems are not very tale tale, I suspect that you are not getting post due to a faulty power supply, do you have a digital volt meter that you can measure the voltage on the power connector on the motherboard.

when you turn it on and it shuts down do you see the cooling fan on the power supply spinning,
if not it is in fact turnning off.
next step is to find out why.

[Vickip]

Have you tried resetting the cmos (assuming you have a jumper on the MB)

Also, it could very well be a PS problem...

If resetting the cmos doesnt help, try a different ps...

If you can be a little more specific on the mobo...ss7 doesnt pull up much info...atleast, not about a motherboard anyway..

Vickip

[DallasDon]

Uh, I got the same symptoms on a new install, after dl windows critical updates. Killed the video DEAD.

Booted in Safe mode, system restore to before the updates, everything back to normal.

I did find that I had not installed the Via chipset drivers for the main board, so the sytstem was apparently running from Windows video drivers.

I have not tried to update yet, kinda afraid to....Weird....

[kopfjaeger]

Thanks for your help Gents,

Don,

That sounds like what happened when I updated video drivers for a PC Chips M598LMR from the driver ftp URL given to me by their tech support. Turns out they gave me the wrong software. Lucky for me I wasn't flashing the BIOS, which is a lot less forgiving. After some serious kludging, I managed to get the machine up and running.

Vickip,

My apologies --first, for not listing in the first place and second, for not being able to give it to you here. I'm on another workstation and away from my workbench, where the box in question is resting in pieces.

Baily,

Following your lead, I switched out the power supply and noodled with the power and power LED switches. I am getting erratic results. I got all the way past spash screen, POST and BIOS (ensuring that the right harddrive was recognized) and a functional on/off button, right back to power-on-with-power-cord-into- the-powersupply (which is bizarre), right back to splash screen and nix. It only seems to vary with which sequence I plug the power cord into the PS. Another variable is jacking / unjacking the FDD, or rotating the button board leads. The main board will work, but I can't figure out why it is acting so squirrelly.

Thanks once again for any suggestions you can provide.

[rpertusio]

Is the CMOS reset jumper in place? (A missing or incorectly set jumper can sometimes cause these symptoms.)

Otherwise, because you mention it being "squirrelly", you could feed it acorns. Or, it could be an idication that something is shorting out on your motherboard/psu. (I expect eagle1 will chime in with this theory as well .) In effect, every time you 'touch' something (add/remove something) you re-position the components, and it works for a little bit.

To test this theory, you can simply tap/move/reposition the motherboard/compoents and see if it 'magically' works for a short time again. An even better test would be to remove the motherboard from the case, and place it on a non-conductive surface (many people use telephone books or wood). If the system works fine outside of the case, then you know that the motherboard (or something else) was shorting out on the case.

- rp

[kopfjaeger]

Update:

As far as I can tell, the main board is a Hewlett Packard Cognac, Intel Chipset, 500 MHz Celeraon CPU, 128 MB RAM (PC 100 I think).

I haven't gotten a BIOS number which would normally follow the initial (not MS) splash screen.

I have repositioned the CMOS jumper (J6?), which was the only jumper that looked like a jumper, much less a CMOS jumper -- for about 3 seconds under power -- then powered down and returned it to the 1-2, rather than 2-3 position. There were no numbers on the silkscreening to tell me which pin number 1 was, so I am using a SWAG (scientific, wild-ass guess).

Power cord into PS gives me immediate power on. At times the on/off button will switch power on / off, but for the most part, once th machine rolls beyond 5 seconds or so, the on/off switch is ignored.

Why, oh why, is this machine going to immediate power-on? I have swapped out PS's and both seem to make both PS and CPU fans whirr quietly.

The HD and Power LEDs seem to go on or off at whim.

After I recover from my New Year's hangover, I will dismount the mainboard and try the entire operation free of the box and see what happens.

See you next year!

KJ

[kopfjaeger]

okay.

It's next year.

Dismounted the board and have it sitting on cardboard. Have tried different power supplies. Have even tried pulling off the button board connector, but consistently the board goes to power on as soon as I plug in the power supply.

Weird. I'd hate to think it's just a bad board. I always suspect that there is something obvious that I'm missing.

Sigh

[John Prophet]

Any bulged capacitors on the motherboard?

Pics of bulged caps

http://www.feistworks.com/3comfix/

http://www.pcstats.com/articleview.cfm?articleID=195

[HeadBand]

a couple weeks ago my dad had this same problem the splash screen would show but then the boot loader would not so i would turn it of and i could not get in to my bios but if i left it set for a minute after i turned it on and it would boot into linux so i decided what clearing the cmos did and nothing...then i unplugged the power and the surge protector and took out the battery to make sure it wasn't drawing power from anywhere and cleared the cmos and it worked
btw he has an hppavillion 7845 with a p3 866 so it could be the same mobo

also you said something about clearing the cmos when it is on...NEVER DO THAT