Can't get new PC to power up

[TJN23]

Hey guys

I was just building up a PC for my brother when I wasn't able to turn it on. I triple checked the front panel jumpers and couldn't understand why there was no power to the motherboard. I'm using a Biostar M7NCD (link here)

The case is a POWMAX CP0329-4HL-5 BK 400W (link here) and the power switch/power LED/hdd LED, etc. lights stem off the power switch which is embedded in the top of the case....I opened up this part to check for loose connections but everything seems to be fine...

i checked just about everything, can anyone give me a checklist as to what I could be forgetting?

tia

Tim

 

[mechBgon]

Here are a couple things to check:

1) try taking a screwdriver and making a direct electrical connection between the motherboard's POWER_SW pins that the case's power button would plug onto. The momentary electrical connection between those pins tells the motherboard to fire up the power supply. If that works, then the case's power button is probably faulty.

2) check that your ATX12V power cable is plugged into the motherboard


PowMax products seem to have a lot of problems, so I'm sorry to hear you have one of their cases and presumably their power supplies. Consider testing with some other power supply if the problem persists.

 

[TJN23]

mech, thanks for the checklist...

the ATX12V power cable is not plugged into the motherboard, and i knew it had to be somewhere, but where? i can't seem to find the damn spot to plug it in...

pics of my mobo can be found here

tia

Tim

 

[mechBgon]

Originally posted by: TJN23
mech, thanks for the checklist...

the ATX12V power cable is not plugged into the motherboard, and i knew it had to be somewhere, but where? i can't seem to find the damn spot to plug it in...

pics of my mobo can be found here

tia

Tim

Ooops, I apologize for misleading you... you're right, there isn't a spot for it on your particular motherboard 😱 Some boards don't use them, like Asus A7N8X-series for another example. I knew I should've taken the time to do a reality check before saying that... grrr, listen to the little voice, mechBgon! 😛

Ok, so try the manual tripping of the power-button pins and see if that starts it up. If not, I'd pull the board out of the case, lay it on cardboard, threaten it a little, and try it with only the bare essentials: keyboard, video, one memory module, CPU and heatsink/fan unit. No drives, no cards, no USB wiring from the case, and see if it will start up like that. If it does, maybe there's some kind of short-circuit situation in the case, such as the springy finger things on the rear I/O shield sneaking into your USB or LAN ports (you could do a visual check for that before removing the board from the case).

Hang in there 🙂

 

[TJN23]

i appreciate the pointers mech, and I was looking through your link in your profile, but could you tell me exactly what you mean by "manual tripping of the power-button pins and see if that starts it up" ?

edit: also when I fire on and fire off the power supply by switching on the " I " and "O" buttons on the back of the exterior of the power supply unit, i can distinctly hear it turn off....a slight "shrrrrreeehhmm" sound so i can tell that the PSU is functioning from that standpoint

TIA

Tim

edit2: i'm off to bed, i'll try tripping the pin connector in the morning, if that works i can probably assume the cases power button is faulty, otherwise, i can assume the motherboard and/or case are dead?

 

[mechBgon]

Originally posted by: TJN23
i appreciate the pointers mech, and I was looking through your link in your profile, but could you tell me exactly what you mean by "manual tripping of the power-button pins and see if that starts it up" ?

edit: also when I fire on and fire off the power supply by switching on the " I " and "O" buttons on the back of the exterior of the power supply unit, i can distinctly hear it turn off....a slight "shrrrrreeehhmm" sound so i can tell that the PSU is functioning from that standpoint

TIA

Tim

I can help with that, you bet 🙂 Instead of this: photo of case's Power Button wire plugged into mobo's Power-Switch pins...

...do this: oooo, that tickles! :Q Unfortunately the screwdriver tip is on the wrong row of pins in this photo, but you see the idea... bypass the case's power button and make a momentary electrical connection between the pins using something made of metal. This helps determine if the case's power button is the problem or not. 🙂

 

[hairygit1]

Try what mech says =
Just make sure the 'pwr btn' wires are put on the correct pins on the mobo, and the right way round. [if yours has a right way]


If you do have to start replacing/testing, the first would be to borrow a mate's PSU. easy to fit, cheap if it breaks.
Then vga card - easy and cheap [get a cheap one just to test it, or borrow a cheap one that works]
if both your ram put in one at a time still give the same results, then it may be cpu/mobo.

good luck

 

[huesmann]

Yeah, IIRC some of the front panel connections are polar, i.e. they do care which direction the plug is inserted onto them.

 

[severtki]

You can also take your PS into just about any computer shop and they have a little device that will test it. If all the LEDs light up on the tester, the PS is good. In my case, it made the little noise you're hearing as well, but there were other problems with it that prevented it from booting the MB.

 

[TJN23]

ok, it's a no go with the screwdriver, i tried every pin with it and nothing....this narrows down my problem to most likely the PSU right?

edit: i swapped in a working PSU and nothing with the power button or the screwdriver. The only jumper cable in was the power switch one (and i tried all combinations for good measure). I took the video card and memory module and out tried out the working PSU as well. Do you think my mobo was DOA? The mobo and CPU were both retail...

TIA guys i appreciate all the help

Tim

 

[mechBgon]

Originally posted by: TJN23
ok, it's a no go with the screwdriver, i tried every pin with it and nothing....this narrows down my problem to most likely the PSU right?

edit: i swapped in a working PSU and nothing with the power button or the screwdriver. The only jumper cable in was the power switch one (and i tried all combinations for good measure). I took the video card and memory module and out tried out the working PSU as well. Do you think my mobo was DOA? The mobo and CPU were both retail...

TIA guys i appreciate all the help

Tim

You don't need to try all the pin combos, just the correct ones 😀 And for your board, that means these ones. And did you try it out of the case lying on cardboard?

 

[imported_raybay]

You can buy a power supply tester for $9.95 at CompUSA, $5.95 at Frys, and $7 to $25 at good tech supply stores. It will be handy the rest of your computer life so is a good investment. A good one will have a series of leds for each aspect of the power supply. Many power supplies will start to fire up or make the case fans turn briefly, but they are still dead and will remain dead.

In the meantime, I would do a rule-out test by trading power supplies briefly with another computer. Does the Powmax PS work in the other? Does the another work in the PowMax. You can use almost any powersuppy briefly, and do not need to install it with the screws. Just let it hang out over the edge of the case, carefully suspeneded of course.

 

[TJN23]

the powmax PS worked in my 3 year old machine, powered it up perfectly, and my 3yr old enlight PSU did not power up this new machine that has been giving me problems...i have narrowed it down to the motherboard and RMA'ed it with newegg, so they'll be sending me a replacement asap...

more to come, thanks for all the help guys

p.s. what are the advantages of setting up the system on a piece of cardboard?

tim

 

[climb4]

p.s. what are the advantages of setting up the system on a piece of cardboard?

tim[/quote]


Just being sure something in the case isn't shorting the motherboard.

 

[VirtualLarry]

I've always wondered a bit about those that recommend testing a mobo on top of the anti-static bag that it came it. Aren't anti-static bags generally conductive on the surface (with some resistive properties too)?
I would think that in extreme cases, that might actually serve to short something out more.

I generally agree, when doing a bench-test of a mobo, put it on cardboard or wood or something. Just make sure that it's not "staticy".

I think that sometimes the pink foam that also comes with a mobo might be slightly conductive too, but I'm not sure about that. In fact, it might be better if it were, because I often use it (after cutting into smaller pieces), for vibration-isolation-mounting purposes, including the PSU. Do you think that it's important for the PSU to have a large metal-to-metal contact surface area against the case, for grounding purposes? Would using that pink foam to isolation-mount the back of the PSU where it's screwed into the case cause any sort of problems or issues with the system chassis ground plane? It has seemingly worked for me thus far though, and certainly cuts down the noise-coupling between the PSU fan and the case itself.