Computer Doesn't Boot

[Ambatim]

Hi Gurus,

I am building a new PC. here is the configurstion.

Motherboard: Intel Desktop D875PBZ.
Processor: Intel P4 3.2 GHz
RAM: BuffaloTech 333 MHz CC 2.5 Non-ECC Unbuffered 2X512 MB (Dual Channel)
PSU: Allied AL-A400ATX.

When I switched on for the first time(with RAM and processor) no fans were spinning, no POST and nothing happened.
Then I looked for any short with case and I found that my mobo was touching the case and I loosened the screws and
everything was OK. There was POST. Then I installed the hard drive and IDE drives. Now when I switch on the
fans spin only for 1 sec and after that they stop. Nothing happens after that. No POST.

But if remove the RAM from the motherboard, then the fans spin continously and there is POST.

Does this mean that my RAM is not working or is there a problem with my power supply not giving enough power for the motherboard
when the RAM is installed.

Any ideas why this is happening ?


Thanks in advance
Mallik

 

[rockerfellerz]

It could be the system buss speed is not set corectly for that memory. Read here:

http://www.intel.com/design/motherbd/bz/bz_mem.htm

If you're going through Hell...keep going... (Winston Churchill)
RocKeRFelLerZ

 

[micker377]

<Then I looked for any short with case and I found that my mobo was touching the case and I loosened the screws and
everything was OK>

Did you fix the short and tighten the screws? Those mounting screws are also grounding screws for proper operation.

 

[Jazket]

First of all, all the motherboards come with the Clear CMOS enabled, which is the pin 2,3. turn that jumper back to the Normal, which is 1,2 and you will see the computer alive...

 

[Ambatim]

If I tighten the screws the mobo is touching the case and getting short. Do I need to put anything (anti static) underneath the mobo so that it doesn't touch the case and tighten the screws ???

I checked the CMOS jumper it is set to 1,2.

Thanks in advance
Mallik

 

[micker377]

How is the motherboard touching the case? There should be stand-offs on the case which only touch the motherboard at the mounting pads on the board. Is this a brand new case, or re-used?

 

[Ambatim]

There are no stand off on the case. It's a new case. Its a APEX TU-150 case.

Thanks in advance
Mallik

 

[micker377]

Looking at the pictures (NewEgg.com), this case has a normal "flat" mounting base. This means you HAVE to install the brass stand-offs that came in the plastic bag with the mounting screws. If the stand-offs aren't there, I'd contact where you bought it and complain. In the meantime, go to a Computer store and get some. Look at the bottom of the board and see how many mounting pads you have (not all of them will line up with holes in case, use all you can). You may have already damaged the mobo.

 

[paparazi]

Ambatim

Just to add to what micker377 said.
The motherboard must only touch the case through these brass or metal clip type motherboard mounting posts and should not be screwed directly to the backplate (how on earth did you manage to fit the I/O backplate? as it shouldn't have lined up if the motherboard wasn't properly raised with mounting posts)
You may well have damaged the motherboard by shorting it to ground BUT!!!! in my experience when someone has done this they often get away with it! and the motherboard after proper mounting works fine.
So, look at the board, depending on model you will see
6, 7, 9 or 10 BRITE SOLDER (holed) RINGS, this is where the "brass standoff's or sprung standoff clips need to be.
Screwed or clipped onto the backplate and lined up EXACTLY with the brite solder mounting points ONLY!!! then obviously use the correct screws (either fine or course thread, check a screw in a brass standoff first) to fasten the motherboard firmly in place.
Suspended, and only touching ground at these points.
Martin


We like members to GIVE and not just TAKE.
Participate and help others.

 

[Ambatim]

Thanks guys for the valuble advices.

Actually I couldn't line the I/O backplate and removed it, to bother about it later. Now I understand and let me try with the brass stand offs and will let you know.

Thanks in advance
Mallik

 

[Ambatim]

I removed the board out of chasis. I put just processor and 512 MB RAM . That's all.
There is nothing else connected to the board except the power supply. I made sure that the voltage is set to 115V. I connected both the power cables from PSU, one 10X2 pin and 2X2 pin to the board. Power supply fan is working. There is thermal compound between heatsink and processor.

The fans spin for 2-3 seconds and stop. There is no POST. But if I remove memory from the board then the fans spin continously and there is POST (I can hear the beeps). I thought that there is some problem with the memory and I purchased new memory and tried . Even then there is no use.
The fans spin for 2-3 seconds and stop

What could be the problem.

Thanks in advance
Mallik

 

[tf1]

The POST beeps are almost certainly because it cannot see any memory. Please check that any jumpers or switches are definitely in the correct position (though usually most motherboards are jumperless these days except for the CMOS reset).

I guess this is looking as though you may have faulty memory.

Regards: tf1