Ok, I've moved onto BIGGER problems.

[ecarmody]

So I was dealing with how to get the OS installed; at least the computer would post, bios access, boot floppy ... ok.

Then doing multiple ctrl-alt-del's for reboots to try and get os to start installing ... now nothing. :(

Last thing I did was get into bios to tweak a change, F10 to save exit, and it exited the bios screen, but did not reboot.

Powered it all down, unplugged, waiting a minute plugged it back in, power switch on, press reset button on front and nothing goes. The case fan does a little jerk, but thats all. No cpu fan, no case fan, no screen activity, no beep (it would alway single beep before).

Would this sound like a PSU issue, or mobo or cpu issue? I don't know what the behaviour is on a bad mobo ... would the case fan still spin?

I've unplugged all devices (HD,CD, floppy), took out the vid card, remove memory, tried just one stick. Still no action from the fans or any signs if life.

I was regularily checking the temperatures in the bios screen and the cpu was a consisten 29/30 degrees.

How do you determine if bad mobo or PSU ? I don't have another to test with.

[chunkylover53]

OK, first thing I would do is double check all connections. Take them out and put them back in. One of the most common things missing or loosse is the 4-pin CPU power connector, which is top left (if you are looking at the mobo with back panel facing to the left).

If not, could be PSU. I assume you are using the PSU that came in the Sonata III, and if that's the issue you might be hosed and have to go getcha a new one. Easier than trying to return the whole case I would assume.

You will probably get more advice this morning.

[shyster]

I have nothing to add, but I will second what Chunky said. Make sure everything is plugged in even if that means taking everything out one by one, and then putting it all back in one by one. Since you are not even getting power likely it means a power cord is off somewhere, since even my broken boards still supplied power to the fans.

[The Wise Monkey]

If the last thing you did was to change the BIOS, then try resetting it by removing the battery. :)

[ecarmody]

Ok, I will pull the cmos battery tonight when I get home from work. I should say that I tried the cmos clear jumper last night with a screw driver; may I didn't do it well/long enough. The battery test though should do it to clear it.

I did google around last night to look for a way to test the PSU. I found this example on how to hot-wire a PSU.
http://www.techwarelabs.com/guides/misc_mod/psumod/

I unplugged everthing but the case fan and tried their approach. Lo ... my case spins! For better or worse I'm not sure. I'd rather have a bad power supply than a broke mobo.

Since the fan did spin, not sure if this means it is working fully or just enough to power the fan by itself but not enough to run the whole mobo. I also found site to test it which basically that same approach, but it identifies using a multimeter (which I have one) to measure the voltages. I will do this when I get home tonight.
http://www.ochardware.com/articles/psuvolt/psuvolt2.html

Here's hoping the battery pull works. :eek:

[ecarmody]

Well ... not have any joy. Cannot get any sign of life from it.

Took out cmos battery, unplug everything, plug back in just 24 plug power plus the ATX 12v, plus the reset sw and power sw and vid card.

No beep, no spin of the case fan nor the PSU fan.

I hot wired the PSU and used my multimeter and site guide showing voltages of the 24 power wires, plus checked most all power plugs off PSU and they all appear to show proper voltages, so at this point it looks like the PSU is running fine. Case fan and PSU fan both spin when hotwired. No plugs connected to the mobo during this test.

Last thing I did was a couple bios changed. Changed two settings, one for limit cpuid max. to 3 - set to Enabled for legacy OS's such as WinNT. I think the other was to turn off hyper threading. When I was saving the bios at that point it froze and has not sparked up since.

The only thing that happens when I press the front panel reset is that the case fan does a little jerk. If I press the reset again, no jerk. Everytime I unplug and plug back in, the case fan will jerk upon pressing front panel power reset button, but only on the first button press. For whatever that means.

I have to start considering to attempt a return of the mobo at this point, unless some more ideas to try?

Eric