computer wont boot up

[Vinin]

So I recently came back from college in New Orleans where I had my computer that I built there running fine. When I get back here to New Jersey however, I plug everything in and when I try to turn it on, it starts up a little and then shuts itself off. I had shipped my computer from NO and had opened it up to check out everything inside. Everything seemed fine, but it still wouldn't stay on. All my fans lit up and everything starts whirring, but then it all just stops after a second, or if I am lucky, it will stop after 15 seconds. My first guess at this would be that the power supply was wrong, so I switched that out, and I am still getting the same problem. If anyone could help me out, that would be great. I will list my specs below.

Note: The computer worked fine in New Orleans using the old PSU.

ASUS A8N-SLI Deluxe Socket 939 NVIDIA nForce4 SLI ATX AMD Motherboardlink
eVGA 256-P2-N383-BX Geforce 6800 256MB DDR PCI Express x16 Video Card (x2) [SLI] (this isn't even listed anymore, they are just vanilla 6800's)
AMD Athlon 64 3000+ Venice 2000MHz HT Socket 939 Processor Model ADA3000BPBOX link
CORSAIR ValueSelect 1GB (2 x 512MB) 184-Pin DDR SDRAM DDR 400 (PC 3200) Unbuffered Dual Channel Kit System Memory Model VS1GBKIT400 link
NEC DVD Burner Black IDE/ATAPI Model ND-3540A link
Western Digital Caviar SE WD2000JS 200GB 7200 RPM SATA 3.0Gb/s Hard Drive (x3 more or less, I have three different HD, but unless they have different power draws, it shouldn't really matter that much) link
Antec Performance I P180 link


Old powersupply
Thermaltake Silent PurePower TT-420AD(DUAL FAN) ATX 420W Power Supply link

New Powersupply
Antec TRUEPOWERII TPII-480 BLUE ATX12V 480W Power Supply link


This is not a review on parts for a machine I will build. I have already built this machine and do not really care for criticisms on the parts. I would just like to figure out why I am having these start up problems.

 

[Mobius]

Ordinarily, the standard fix for this issue is to remove the main power plug from the motherboard, and put it back into the socket, seating it strongly.

But, as you said you already swapped the PSUs, one would think you had used sufficient force to ensure the power was getting to all points on the Mobo.

Humour me: wiggle that main power connector into the motherbaord a bit and try booting again.

 

[marco324]

try reseating memory and rest of your cards i had the same problem
this worked for me

 

[ches111]

I agree with marco,

Reseat EVERYTHING!! By reseating I mean take the card out fully and plug it back in again! This is better than just pushing on everything as somethings could have shifted.

 

[Vinin]

I've tried reseating everything, nothing happens.

 

[ches111]

Are you getting POST codes or BEEPS?

If you are hving certain issues your MB will tell you about them. Memory failure your MB will tell you. CPU failure MB tells you and so on....

If you are getting POST codes decode them using your MB book as a reference.

 

[Vinin]

I don't even get far enough to get a POST or warning failure. The farthest I get is to the BIOS initialization screen at which point everything just shuts off, theres no error code or anything. Most times, I hit the power button and my blue LEDs come on but then shut off immedietly after. These are the blue leds in my fans. I don't get far enough for an error, it just simply shuts off.

 

[ches111]

That sounds bad.

You might have a MB failure if you are not even hitting POST.

Are there any diagnositc LEDs in the machine?

Some machines don't do verbal POST codes they actually have a series of blinking lights inside or even a number LED that posts a number.

 

[Vinin]

I don't think my mobo is it, all I have is a single green LED light that signals when there is power, and that is fine.

 

[ches111]

Power to your MB and it getting through a POST is two different things.

Had you not replaced the PS, I would have suggested that. Since you are not even getting POST codes of any sort and NO POST then I would look at the MB next!

 

[mulciber]

Here's my ballsy fix for this:

Remove all components from the case.
Find a Hardwood table, or glass table. It is imperative that this is a nonconductive surface.
Position motherboard on the edge of the surface. Position powersupply in a way to allow it to easily reach the needed connectors. Make sure that the powersupply does not touch the motherboard.
Seat the CPU on the motherboard.
Seat one ram stick on motherboard.
Seat graphics card, or use onboard graphics.
Clear CMOS jumper for good measure.
Connect the power switch to motherboard, and fire it up to see if it will POST to screen. If it does, add components until all components are connected outside case. Then reassemble inside case. If not your ram, mobo, or cpu are broken or they/a power connector is not connected correctly.

 

[kshipper]

Check power connections to those graphics cards and check that extra 12v connection to the motherboard...you know the one that is 4 pin connector with yellow and black. A system won't power up for sure if that is disconnected. While checking extra power connections to the graphics cards insure that each card is powered by a separate rail to insure they are getting all the juice they need.

I can also assume that you visually see the main cpu fan heatsink is turning as soon as you press the on button. That too can interfere with a startup.

Try to remove as much stuff as you can before you do all the open surgery with the motherboard right out. So---try it with only one video card and one stick of ram. No add in cards at all. Check for anything loose underneath the motherboard causing a short. Check the switch on the back of PSU---it is set to 120v right?

Check that power connection for the power on button in the mobo manual----it's right too? Reverse it the other way and try---work any different? Reseat the CPU is another option but that would mean re-doing the thermal grease too so go ahead and do that if you have extra thermal grease.

As the last resort you can what the other poster suggested---mobo out on a non conductive surface with only CPU Memory installed---you should get post beeps because you dont have a video card installed---that's a basic test.

I have to disagree with him on the POST beeps if you have a bad CPU---I think you won't get any beeps with a bad CPU. But you must have some kind of a working cpu if you can see some video that it is trying to post.

 

[Vinin]

thanks for the help guys but I figured it out.

Basically it started out as a bum power supply, but when I moved to a new working one, I find that my power supply just doesn't have enough juice to power everything. So I've got to get to upgrading that eventually.

 

[kshipper]

Glad you figured it out. So...removing all the extra cards helped to figure that out?

 

[Vinin]

yeah it did, everything worked as I stepped through until everything was in. Taking out a video card though, it worked, and even when I switched the two video cards it worked. Then with one HD and two cards it worked, so I figure it is power draw.