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New MB, CPU, PS, & memory; won't boot.

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20 replies

by silverback

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I was working on a computer for a client, and replaced mobo, cpu, power supply, CD Rom, and memory. Reinstalled all other components. When I attempted to power up the computer, it simply didn't boot--didn't even attempt to run the BIOS. I checked the PS, all values are w/in range. I attempted to boot with no cards, no memory installed. Didn't even get a beep code. I'm beginning to think that either the mobo or cpu is faulty, but how can I check?

20 replies

by sgt_shultz

only with expensive test equipment. at this point, you need to swap in either another motherboard or another cpu to test imho. i would look at mb website. surely they have troubleshooting steps for dead board...

by silverback

I was already ahead of you on this one. I had already ordered a new CPU/mobo combo. They failed in the same way. I had a mobo standoff placed incorrectly. Doh!!!

by thechas

This may be too obvious, but check the setting of the clear CMOS jumper.

Many motherboards ship with the jumper set to clear and will NOT boot until you set the jumper back to normal.

I have had similar problems with socket A systems. I almost always need to clear the CMOS in order to boot into BIOS settings so I can properly set the CPU speed.

Is the RAM properly matched to the CPU?

Is 5 volt standby power getting to the motherboard?

Is the power supply set to the correct line input voltage?

Chas

by silverback

Everything was appropriately matechd and functioned as advertized. I had a mobo standoff placed incorrectly. Doh!!!

by mthood

1.)Make sure your AGP Video is properly seated. They tend to be hard to seat.

2.)Check the speed of the Ram and the MB Pin outs for Ram Speed do they agree?

by silverback

Everything was appropriately matched and copacetic. I had a mobo standoff placed incorrectly. Doh!!!

by bart777

Let's back up one step and verify that the the case connections are correct. If the power switch is not connected to the right pin set it won't do anything at all. If the book did not come with the MB try going to the web and looking it up.

It may be obvious but I have missed little things like that before.

Also make sure the this is not one of those MB's that has 2 power connectors to the board. Some have the traditional long connector but also have a 4 pronged connector as well.

Just a couple of ideas for you to try.

Good luck.

by silverback

I appreciate your response, but everything was connected correctly. I had a mobo standoff placed incorrectly. Doh!!!

by otl

Saw this once, MB was grounding to the case. check clearances all around the board. Could be grounding out the power.

by pierrejamme

My favorite is this, make sure the voltage on the AGP card matches the Mobo. this mismatch will cause this problem. Take out AGP and put in a borrowed PCI video card to test this out.

by silverback

Let me add a little more information, here. The mobo is a Fujitsu-Siemens D1675 socket 748 with an Intel P4 1.6gHz CPU--yeah, a little low rent, but myclient is a non-profit, and pennies *DO* count.

Case connections are right, and voltages from PS are okay. When I hit the power button, the CPU fan spins, hard drive spins, and nothing else happens--NOTHING. Swapping PCI video card for AGP did nothing--like I said, I don't think it's even getting far enough to run the BIOS, since I don't get any beep codes on power-up.

I appreciate all the responses, and I keep looking for something more definitive. In the meantime, I have ordered another mobo/cpu combo to do some swap-outs. Please keep the responses coming.

Silverback

by daybreaker

You might try moving the memory to different slots if the M/B has them. Also, check to see if the memory needs to be in specific slots. Also, disconnect any external peripherals, usb, scsi etc. I've had a system refuse to boot with a usb hub attached. One other thing to try is disconnect the hard drive and power up. If you get it to display cmos, the drive may have a problem. good Luck

by silverback

Swapped out memory sticks, and moved them to all available slots. No joy.
I had a mobo standoff placed incorrectly. Doh!!!

by rcom

If you don't have the manual for the board yu can probably download it from the OEM website.

I allways try the motherboard outside of the case first before going through all the trouble of installing it. I use a motherboard box to setup on and connect only a power supply, RAM and video. To start it just tap a screwdriver to the same pins the the power button connects to. See if it boots. This way I can test the board to make sure it works.

If not remove the video or ram, you should then get beep codes.

Sometimes we just have to start from stratch and make sure something wasn't overlooked. Allthough you may have built many systems take the time to read and follow the instructions.

by int

Put every component out of the computercase and try again

probably you have a case thats making a shortiche with the components to the iron

INT

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