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New mobo - not booting

Ok here goes...
CPU fan on the old mobo died out and the BIOS popped up. I may have changed some settings before it permanently shut down.
Decided it was time to upgrade so I bought a new Mobo/CPU combo.

Mercury KVM266PM-U
1 stick of 256 DDR RAM
2 HDs (1 master, 1 slave)
Mobo has built-in VGA but also has an AGP slot, I've tried booting with video card in and out (only built-in), not sure if I should be using an additional video card with a mobo that has built-in VGA.

Bought a new PSU and after several days, finally connected the front panel switches correctly.
Power switch turns the system on. PSU fan works, CPU fan works, CD drives light up, HD LED is permanently on. Floppy drive light is either permanently on, or with the cable flipped, permanently off. Does not read even with bootup floppy in, either way the cable is hooked up.
Not a single thing shows up on monitor, using either built-in VGA alone, or with AGP video card. Have tried two monitors, each of which to my knowledge, are working fine.
No beeps from speaker.

After a bit of research, I'm considering clearing the CMOS but want to know from others if this is recommended for a situation like this.

Also, is the BIOS stored on the mobo or the HD? Would my previous settings be stopping the system from booting properly?

I'm also a little confused about the proper way to clear the CMOS, if this is an option for me.
I know the proper jumper and where it is, but do I leave it in, power off, for 10 minutes or more?
Or is it better to boot the system without the battery?

Thanks to any who offer advice.

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Clearing the CMOS [BIOS][setup]

In reply to: New mobo - not booting

simply sets it back to the default setting, so should not cause any problem.

Use the jumper, that's what it is designed for. Removing the battery could lead to loosening the connection and creating other problems.

The maual should tell how long to leave the jumper in the clear position with power off. Give it a good 20 minutes, just to be safe. Got nothing else to do. LOL

Lets disconnect all drives, both power and signal and work with a minimum of hardware.

The BIOS is stored in the CMOS chip, on the mobo. Sometimes called the RTC [real time cllock] chip. Virtually always near the battery.

Can't do much re the BIOS until you get some video. To use a VGA card you would most likely have to disable the onboard video in the BIOS. Maybe a jumper on the mobo, but not likely but again RTFM LOL. In the meantime leave the AGP card out.

If you installed the mobo in a case that the former mobo was in, are you certain that you didn't leave any hex standoffs on the mounting plate that are not lined up to mounting holes in the new mobo? Could short out the artwork and cause problems.

Get the video working and then we can solve the floppy problem after that. One issue at a time. HD light permanently On is not normal. Certainly should not light when you disconnect the power and signal to the drive.

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Re: Clearing the CMOS [BIOS][setup]

In reply to: Clearing the CMOS [BIOS][setup]

Thanks Ray,

I'll try all that when I get home tonight.
Sorry, should've been clearer on the fact that the HD LED is permanently on only when powered up. Not sure if it should flash intermittently or not.
Manual says to leave the jumper in CLEAR for the CMOS for a few seconds, which I've tried. So I'll give 20 minutes a shot.
I also discovered that my video card is not an 8xAGP as the slot requires, so I shouldn't be using it all.
Will update tomorrow.

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I looked into some of the mobo info

In reply to: Re: Clearing the CMOS [BIOS][setup]

at one site. It shows that the AGP slot supports 4X. Probably also 8X.

Possibly will not want earlier than 4X because they use a different voltage. However, normally if there is a backwards compatibility limit with the AGP slot, the mobo will make it clear. Both the 4X and 8X use 1.5 volts. The earlier use 3.3 volts.

My Soyo mobo had a labeled tape on the VGA slot saying to only use 4X or 8X.

A few weeks ago someone tried a few minutes to reset BIOS and it didn't work. Later tried for a longer time and it worked.

Of course, nothing really says that your BIOS is part of the problem.

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Re: I looked into some of the mobo info

In reply to: I looked into some of the mobo info

I can't figure it out.
I tried clearing the CMOS for a good hour, rebooted, same as before.
Got down to the basics with only the HD connected, still the same. Did notice this time that the HD seems to be doing something and the HD LED goes off after about 30 seconds.
Tried booting without RAM, no beeps.
I even tried unscrewing the motherboard, checking for unused connectors on the back that may be touching the board but there weren't any. Put in a few extra plastic cushion pins just in case.
I think I may have to resort to going to a technician unless there's anymore ideas.

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The basics DO NOT include

In reply to: Re: I looked into some of the mobo info

having the hard drive connected!!!!!!!!!!

Get down to the absolute minimum. If it doesn't work at that level adding anything else is simply a waste of time.

With the front panel pins all connected properly, the CPU and HSF in, one stick of memory, no keyboard, no mouse. No PCI or other cards. No floppy, no optical drives nudding!!!!!!!

Noticed lately that many mobo types [their BIOS] do not beep when things are OK, just when problems. This makes this first level of testing difficult. Should get beeps without memory, without CPU. Can't be without video because it is built-in. You apparently get no beeps under any circumstance.

In this configuration then plug the monitor into the on board video out connector, and power up. With luck you will get the firsat video screen giving the video and BIOS info. Don't get that, then must try a different stick of memory, if that doesn't work its either the CPU or mobo. Are you absolutely certain that the CPU is properly installed????

Improper installation of the CPU could be a problem by the CPU getting hot very fast and the mobo shutting the system down. But in your case it seems that the power is staying on.

Just an aside for future assembly & mounting info. The mounting holes on the mobo that have a printed circuit ring around them are all connected to each other via one of the inner layers of the mobo.[the ground plane]. Best that each of these is mounted via a metal hex standoff to the metal mounting plate. Purpose is to make an equipotential ground plane at the high frequencies of the noise that the digital devices put on the busses. The good RF ground is created by the close intimate contact between that ring and the hex standoff. The mounting screws simply provide the pressure to maintain that intimate contact. [good design practice NEVER allows the screw to carry any type of current]. Thus the fiber washers that they provide are not for insulation they are to put under the head of the screw to prevent the head from damaging the printed artwork around the hole while the screw is being tightened. [the hole is a "plated through" hole that joins the top and bottom ring and the inner layer].

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