New mobo - won't power up

I hope the good troops at MG can help me again. Just replaced my mobo (with same type and model - previous one had gone to mobo heaven). Reconnected everything and turned on the power supply. Green light on board - that's good. So I hit the computer on switch. Came on for about 1 second and went off. Several tries produced same result. Should mention that I reinstalled the original processor. I'm sure it's something obvious that I'm overlooking. Any tips, suggestions, shape-up punches, etc.? Here's the particulars: Asus K8V with AMD64 3000+, Seagate 160GB HDD, 1.5GB memory and running XP Home with SP2. Had taken it to the local gurus for checking out when it went belly up (wouldn't shut off unless I turned off the PSU). They found the MOBO to be bad but couldn't check out the processor because they had no good boards with socket 754. To save money, I decided to put the processor back in. Could that be the problem?
Thanks for any help.

 

I believe at least the fans should continue running even if the cpu is bad, i would clear cmos, just use one stick of ram at a time till i could get it to at least post, do you have another power supply to test with? ed

 

Does it require the 4 block power connector as well as the Multi..

 

Have you got that board fired up yet? ed

 

Power supply checked out good when in the shop. I'll try your suggestions and post an update.
-SgtRon-

 

Yes it does.

 

Agree with TimW. There might be shorting out the back of the mobo & the case. I always build the barebone: cpu, mobo, ram &/or video if no onboard, on the box it the mobo comes with. If it works, i'll put it in the case.

Also, your psu might be dying. Or the board wants more than normal power. i.e. 400w. What make & model is it? Or how many watts?

 

I'm sure the mobo isn't shorting out. Only contact to case is the mounting studs. As to the PSU, it's 450W. Has been doing little more than idling with this build. No signs of overheating, etc.
Tried Tunered's suggestions (resetting CMOS and installing RAM one stick at a time) - - no change in behavior. Where can I go from here?
Thanks to all who've responded.

 

Definitely take it out. If it works, you'll thank yourself later.

Also, rebuild everything again. Only this time, carefully check for damage. A table/desk lamp & a magnifier would help.

When you reset cmos, you need to disconnect power cord & press power button on pc first to discharge remaining power. The fans & lights will go on & off. Then short the cmos jumpers & take out the battery for a min.

Did you connect TWO power cables to the mobo? 4-pin & 20/24-pin.

lol at TimW at age 1. I'm age 0. Beat that.

 

Had a similar problem with an ABIT board and it turned out to be that I had mal wired my USB. The Positive was on the Negative... worth a check that all wires are connected properly.

 

Sounds like possible dead CPU, the only way to comfirm is to install it in a Known working system

I have a couple of dead socket 939 CPU's when they are installed in my DFI Ultra D mobo it will try to boot, all fans etc work for aprox 1 1/2 seconds then nothing all goes poop except a couple of on board leds remain lit

Ive seen a couple of system's that had a short/grounded MOBO, the systems would fire up fans spinning etc just no video.

What killed the old MOBO, when major hardware like a MOBO/PSU takes a dive it can take other hardware with it

 

Not sure what killed the board, Asus. One day I'd shut it down and left the room before it was completely off. Came back a couple hours later to be confronted with the "windows is shutting down" screen. (had a momentary power outage in the interim) Tried to turn it off with the power switch on the case with no result. Had to turn off the PSU switch to get it off. Should mention I use a surge suppressor on it, too. Must say, you guys don't make the health of my CPU sound the greatest! Will follow Akhilles' suggestions in the morning and see what happens. Thanks for all the help, troops.

 

I hope your CPU is fine
If I had a 754 socket system I'd offer to test it, sorry no got.

Try this remove your CPU, then power up your system, if your fans stay powered up without the CPU thats another sign that your CPU is in fact dead.


You might while the cpu is off give it a good cleaning & try it again
Ive seen cpu that were left for dead come back after good cleaning

When confronted with "windows is shutting down screen" this may have just been a freeze up
Two thing come to mind, First PSU problem, or stability issues

When you tryed to power off using the case switch did you try holding the button in for at least 4 seconds?

What exact brand PSU do you have?
There are many brands that are notoriously problematic
I know you had someone test it but I wounder how they tested it?

I dont mean to raise question of a repair shops abilities but if it turn's out your CPU is dead, my First Question would be "Was the MOBO really dead?"
then the next, PSU?

 

Tried your suggestions, Asus. Removed the CPU and hit power switch. Nothing, no response from fans. Oh, and the PSU is a Diablo 450W. Re the board; the folks at ASUS tested it and apparently found it beyond redemption because they sent me a new one (old one still had a couple months of warranty left).
At this point I guess I can assume the CPU is ok? Or is my reasoning flawed?
Thanks for your help.

 

CPU might be OK

When you tryed booting with CPU removed did you hear any beep codes?
You do have onboard speaker? if you do and no beep codes are heard this is sign/symptom of a short
A short like skinned wire/mobo stand off in wrong position/ loose screw floppin around in your case or similar

This is also a symptom of a underpowered or even bad PSU
I have to tell you, I'd never buy a Diablo anything
I did quick search of your PSU I didnt see any info on a Diablo 450, I did a find 550 info, it'a only 20 amp on the +12v rail which IMO isnt enough juice for your system, and you have a 450 model so your +12v is even less

 

once a friend of mine(very able) was trying to swap my proc and accidentally hit one of those mini little iddy biddt square things usually beside the proc and fan, not to mention all over. Anyhoo he scritched a little square thing and that was it...No power!
Possibly could you have done the same thing? It is very common, and hard to admit, but maybie?
He some how fixed it I was sure I had a new mobo coming....but he managed to solder it back to life.
Dropping a screwdriver on a mobo is a "Murder Death Kill" and even Arnold cant help you if thats the case, Nor can Rambo

 

I know what you're talkin' about, JAZAGOD, but as a retired techie, I'm very careful around anything with chips on it. If I have anything metal in my hands, I move very slowly and deliberately. Don't think that's the problem here, but thanks for the heads-up.

 

No prob, I hope you can get it figured, I can only imagine what your dealing with

 

Nope, didn't hear any beep codes. But then my hearing ain't all that good anymore and I haven't heard any since I first built the machine! Vis-a-vis the PSU; I was going to comment that it was working fine until this unpleasantness. But then I guess everything works fine right up til it quits. You're just giving me all kinds of good news! But I appreciate your expertise. What's the best way to check out the PSU? I'd go blind trying to check the voltages on all the myriad of connectors!

 

do you have a volt meter? Techies should have those toys..(wish i had one) . I have a feeling after rereading this thread that its your PSU. I think your proc is fine,andc all else is well. try another PSU . I really hope thats it...Alot cheeper

 

Make sure the clear cmos jumpers cap are in normal position.

Did you take the board out?

 

Haven't taken the board out yet for testing; it's such a hassle trying to get the cables to reach it. Power cables are just long enough as it is. And the cmos jumper is definitely in the correct position. At the moment, I'm shopping for a PSU. But, much as I dread it, the next step will have to be the removal of the board and firing it up "outside".

 

Tim, you're a lifesaver! That will save me a lot of searching and needless probing!

 

Ok, I checked all the PSU voltages and found them to be normal. Removed the mobo from the case and connected power cables as well as the IDE cables and connected the HDD with it's power and SATA connections. Results of hitting the power switch remained the same; sometimes a momentary flash of movement from the fans, but most times nothing. Should mention that the PSU fans spun up normally when the PSU was disconnected from everything. And, yes, I checked carefully the switch connections to the board. Looks like I'll be buying a CPU. Thoughts?

 

Just because the voltages are fine on the meter does not necessarily mean that under load they will remain fine, I like some of the others would try a PSU swap, cheaper and it is always handy to have a spare PSU, not to handy having an extra CPU though. Good Luck I know its frustrating

 

Does it just power on & off with all the fans & lights going on & off immediately as soon as you power it up? You should only have cpu, mobo & ram. Video card if no onboard video. Also, a pair of speakers for beep codes.

Did you check the mobo site for cpu support? Needs a bios update?

Yes, always have a psu as a backup. Can be generic with high wattage or brand name with low wattage.

 

Yes, when there's any movement at all, the fans just go on and off immediately. No, I didn't check for update on the BIOS because I didn't see how that could prevent it from coming online. Will do that.
For BCGray; yeah I realize voltages could be different under load, but it shouldn't be loading down that much. However, it's a good point - think I'll try checking some of them as I hit the on switch. Nobody ever said electronics was always fun!

 

Just checked PSU voltages under load (discovered that if I repeatedly pressed "on" switch the power would stay on for a few seconds). All voltages were ok.
Reset CMOS and removed battery for a minute. Upon normalizing, tried again; same results. So from all the tips I've been given here (for which I thank you all), I guess I'll be buying a new processor.

 

Just to let you know, i have checked several bad, cpu's on the same mother board and did not have the problem that you are having [ not the same board as yours]. Im not convinced it is the cpu, i still believe the fans, cd-roms, hd's, should still power up regardless of the cpu being good or not. Maybe it is the cpu, but im betting on the mother board. Im sure you will let us know, quite interested in finding this one out. Good Luck. ed

 

I know where you're coming from, Tunered, but from everything I've read there should be beeping from the speaker when the mobo/CPU combo is fired up without any RAM. In my case there's only lots of silence. I think I've ruled out everything but the CPU. The board is brand new from ASUS. (yeah, yeah, I know - doesn't mean a thing. In fact I had to RMA my first board right after building the machine) Still - - - ?? I'm open to any suggestions.
thanks, guys!
Addendum: Should have mentioned in my previous post that while I was checking the PSU voltages the fans were spinning merrily and the purty leds were flashing!

 

Just for the record, bad mother boards are silent, cpu's are usually the last to go. I would hate to be in your spot, I hope it all works out, please keep us updated. Thanks. ed

 

The reason some of us aren't convinced it's the cpu is that modern cpus can withstand more abuse. Since yours wasn't & isn't overclocked or damaged, we are still not convinced. However, a bad psu can damage a cpu, or any other parts in the pc.

A pair of speakers would be in order. Also, look at the mobo manual for troubleshooting.

 

Food for thought: a while back i sold an am2 board + ddr2 memory to a guy who complained he pulled his hair out cuz it wouldn't post with his x2 dual core cpu. It was ok with single core. He had a store look at it & they updated the bios. It's been working since. I couldn't believe ASUS would release an X2-ready board that couldn't boot X2. They removed the original buggy bios from their site.

 

Interesting. Unfortunately, I can't update my BIOS until I can get it to power up. Really appreciate all the time you guys are putting into this. Have ordered new CPU from Newegg. Any way I could check out the board while I'm waiting? There are so many ways a board can go belly up, I don't know where to begin.

 

Well i guess when its all said and done, you can return the board and get one that will work, at least you will have a new cpu. ed

 

Ok, received the new CPU today. Installed it and guess what? - same results. So I'm ready to hear a chorus of "I told you so"! Before I call Asus for yet another RMA, though, I'm taking the board in for testing to make sure. Boy, these computers sure are fun ain't they?!

 

Well, finally got the board tested - the shop had a sewer back-up and was closed for a few days. Board tested good so I reinstalled it with nothing connected except power, fans, switches, monitor. Turned on PSU switch and was presented with the sight of all fans spinning and lights blinking, just like the start of this whole debacle. Could only shut it off by using the PSU switch. Checked the case Power switch with Ohmmeter and found it to be working fine. Also checked the voltages once again while everything was under load and found them all normal. Oh, and sometimes when I turn on the PSU switch, nothing happens!
Just for kicks, installed the 3 sticks of RAM one at a time, applying power each time. No change. Also, there has been no beeping from the case speaker through all this. Speaker also checks out. So here I sit; the board is good, the CPU is good, the power supply is good, the RAM is apparently good. It should be cooking just fine. So why isn't it? I'm at my wit's end. Hope someone can help.

 

Sorry don't want to back track the whole thread. Can you post the parts & their ages?

 

If you mean the computer parts, here they are: ASUS K8V, Athlon 64 3000+ both brand new and check fine. PSU is 450W Diablo, 1 1/2 yrs. old. RAM is Crucial (3 sticks; 512MB ea) DDR 3200, likewise 1 1/2 yrs. old. Problem occurs regardless of whether the HDD and RAM are part of the equation or not. And, even with everything connected, the monitor indicates it's not getting a signal and there are no beeps. I'm stumped!

 

Then it could be either the psu or ram.

Connect mobo to pair of speakers, power on, & listen to beep code.

 

Ok, connected a pair of speakers. All I get is the initial "clunk" when power is applied.

 

Thanks for all your help guys. I really appreciate it. Tim, I already went through those steps with no results. I neglected to mention earlier that the power led flashes and the HDD activity led is steadily illuminated. Does that bring anything to mind? I'm really lost here. (if I had any hair, I'd have pulled it all out by now!) Thanks again for all the kind help.

 

Wish it were so. No jumpers have been changed since I got the board back from the shop, and it worked fine there.
Getting late; I'm gonna call it a night. Check in in the morning - - -

 

Onboard Diagnostics/Beep Codes "Can Not be heard on external speakers"

The MOBO need's to have a onboard speaker connected to the front pannel header of the MOBO to hear the Diagnostic Beep Codes

If your Too Lazy Back track, Your probably to lazy to read the whole thread
Maybe you shouldnt bother Posting