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Any Experts on Front Panel Connectors Please?? 3

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eponymous

ISP
Jul 22, 2004
92
GB
Want to put IBM Netvista A40 micro-atx in an atx case but need to decipher proprietory 8 pin Power LED connector??

Is anyone able to identify each of the 8 pins please//tell me how to obtain that info?

Many thanks,
Denis
 
You probably have cleared the CMOS. You wouldn't be able to see any change.
It can be the CPU, M/B, or memory. Or some combination of the three. Usual step from a diagnostic standpoint would be to through a logic probe on something with addresses running around and see if the cpu is clocking addresses out. Then to look at data lines and see if there is any changes there.
If not dumping out then look for clocking in to see if there is a problem with crystal or possibly power good.
If CPU appears to be putting stuff out then memory becomes a factor. Normal BIOS is to run a quick memory test but before it gets there it sets a stack location to store return addresses. And if it can't return correctly the processor goes into "neverland". But it has been years since I looked into the machine language of the BIOS so I can't be sure that the IBM is still following the original specs.
And I had one of my netvistas upchucked with similar problems. Had a spare board, so plopped it in, and never looked back. Sometimes it just isn't worth it to fight a problem for hours when the entire machine I robbed the spare from cost $100. I sometimes have fought the problems for education, but the brain is filling up, and so I am becoming less inquisitive.

Ed Fair
Give the wrong symptoms, get the wrong solutions.
 
No question it could also be a cpu. I have also seen a cdrom stop a computer from booting. Sometimes ram too, it could be one of dozens of items. So it could be the cpu.

If you can borrow another cpu from someone, doesnt have to be the same, long as its same type, it could be slower for instance. Anyway if you could borrow one from a friend that would be a good plan.
Where you bought it from you could tell them if they can get it running you would take it back?


Good advice + great people = tek-tips
 
EdFair and Garebo,

Many thanks for this. Its clear that the variables and complexities have both taken me out of my depth and will generate enough lines of enquiry to render further investigation no longer time efficient. Clearly, simply testing with another cpu is the obvious next step.

It will also provide an opportunity to retest the original Asus CUV4X. On the basis of no beeps someone in the Asus forum diagnosed the mobo as dead. I now see there are similarities in as much as it suddenly ceased to post. So there is a chance it could be a cpu problem. It would be a real bonus if the no beeps was the result of a cpu failure safety measure that cuts in prior to the beeps activating - and that it was the cpu all along and the original mobo is still fine.

Thank you for giving me such excellent advice to reach this point. It has been clear, informative, useable and systematic. I will of course let you know the outcome and keep my fingers crossed that it has been the cpu after all.

All the best,
Denis
 
eponymous, i would just, for your sake, like to make absolutely sure you know the 2 boot pins on the 8 pin configuration. Its the last 2 pins, right?

Now there is a difference between touching the last 2 pins with a screwdriver and doing it thru the power on\off button. If the power\on\off button is damaged then your computer may not boot, where, with the screwdriver, it will always boot, provided it was going to boot in the first place.
So i just want to hear from you that you have tried the screwdriver? Just to make sure, for sure, that we have tried all there is to try.
Also, do you have access, yet, to the motherboard manual?
If so, look to see if there are any jumpers that can be manually set on the motherboard. I, for one, am not quite ready to call it a day, and i know others would stick with this a while yet, lol. We dont give up!


Good advice + great people = tek-tips
 
Garebo,

Many thanks for this. Will simply give you the results of the boot pins test as not sure what to make of it.

1) 0 pins - switch on with PSU on/off at back of PSU : Powers up /logo without any pins breached (i.e unbreached = on??)
2) pins 7-8 (power button) : briefly powers up/logo flashes/shuts down (i.e breached = off??)
3) pins 5-6 : briefly powers up/logo flashes/shuts down (i.e breached = off??)
4) pins 3-4 : powers up/logo appears/stays on (i.e breached = on??)
5) pins 1-2 : powers up/logo appears/stays on (i.e breached = on??)
6) connect power switch to pins 7-8 :

- switch psu switch on – nothing happens (off)
- press power button - powers up/logo appears/stays on (i.e = on??)
- press power button for few seconds : shuts down (i.e = off??)

a) Power button appears to be behaving normally??
b) Still puzzled as to which are boot pins??
c) Not at all sure computer has booted yet?

Re: manual – have located hardware maintenance manual unable to trace user manual. High level of detail in certain areas whilst paucity in other areas better covered by a user manual. Btw no cpu jumpers.

I’m still getting myself organised around trying CPU out on another mobo. Without wishing to tempt providence guess the PSU could also be a contender. Very many thanks for your staying power and encouragement - is much appreciated.

All the best,
Denis
 
ADDENDUM

6) connect power switch to pins 7-8 (above) only applies if power button pressed immediately following psu power switch.

This addendum describes what happens if a short pause is left after turning on psu power switch:

- turns on of own accord (i.e. with power button off) powers up/logo appears/stays on

Please note difference between pins 7-8 breached and pins 7-8 connected to power button :

- when pins 7-8 breached : briefly powers up/logo flashes/shuts down (i.e breached = off??)
- when pins 7-8 connected to power button : powers up/logo appears/stays on (irrespective of whether power button on/off and power button does shut down) [(i.e connected = on??]

Hopefully this will help fathom:

- role of respective pins and whether connected up properly
- whether problem with power button or psu??

Let's hope the contrasting behaviour of the power button v breached contacts - and the puzzling way on/off works - holds some clues.

Many thanks,
Denis
 
I think i understand what you are saying.
How about trying this, unless you have already done so.

Dont have anything connected to any of those 8 pins.
Now either connect the power on\off switch that is on the front of the computer to pins 7 and 8, or use a screwdriver and do the same thing, hold the screwdriver on pins 7 & 8 until you get something on the screen, then take screwdriver off the pins.
The 7 and 8 pins, i believe, are the last 2 on the right if you have the I\0 ports of the motherboard facing you.
In other words, with the connecting ports, keyboard, mouse, usb, video, etc, etc, directly in front of you, with the motherboard face up, then the front panel connection is at the very back, right? Roughly opposite the parallel port connection at the front.
Looking at it this way, the 7 and 8 pins are the last 2 on the right, right?
Im pretty sure we are in agreement here, just wanted to make sure, thats all.

And you are right, they have a ton of info but very little when it comes right down to the front panel wiring itself. Its because IBM sells these machines as office machines and doesnt want people messing with them, lol. They want only authorized repair people to know.
I have 2 customers with these machines and i am gonna stop by and get the correct setup for you from one of these.
The units i am talking about are different from yours, but i am almost certain the front panel connectors are identical. Like i said, they are across from the parallel port connector, a single black plastic connector with 8 pins. Again, the last 2 on the right are the on\off.


Good advice + great people = tek-tips
 
Okay, my mistake.

I have a few different posts in a few different forums, all dealing with netvista.
I see now yours is a bit different model and i see on page 39 that your power connector is number 11 on the pdf book of yours.
However, everything else i said still goes, its only the location is a bit different, it is still likely pins 7 & 8.
So refer to my post above.

I think we are going to need to start right from scratch here.


Good advice + great people = tek-tips
 
Garebo,

Many thanks for this.

It looks like we are referring to the same diagram. No 11 is the power connector and No 5 the power led connector. This URL will take you direct to the diagram:


Using the same orientation as the diagram, the I\0 ports are on the left-hand side. The power led connector is in the right-hand corner and runs parallel to the top of the board. It contains a single row of 8 pins running from left to right with pin 1 nearest to the I\0 ports.

This is the sequence of events:

1) Power off - nothing connected to any of the 8 pins
2) Switch power on from back of PSU - nothing connected to any of the 8 pins:

- fans start
- powers up/logo appears/stays on

3) a) & b) alternative tests with psu power turned off/on and run separately from scratch:

a) Breach pins 7-8

- computer shuts down

b) Connect pins 7-8 to power button

- computer continues to be powered up/logo showing/stays on
- depressing power button for a few seconds shuts down in usual way.

Have no idea whether this is expected to happen or not. Maybe without the power button connected the machine is perpetually “on” … until connected to the power button and its default “off” position?

- However, what I had pictured from your instructions was that things would start from an “off” position until the “boot pins” were breached. Also, am still not sure that the machine has booted yet??

Its very kind of you to check things out with your customers to get the correct setup as, without things booting, its still difficult to be absolutely sure whether the pins have been correctly identified yet. This will be extremely useful and definitive information. Once again, very many thanks for your excellent help.

All the best,
Denis
 
Mine crank up when the mains are activated, but shut down several seconds in with nothing connected. But if I recall correctly I had one at a customer's office that powered up and remained on until I shut down windows after the bootup.
The power on with power switch inserted is correct operation, as is the shutdown when the power switch is held down for several seconds (3 to 5).
Don't know the interlock timing, but suspect that you need momentary contact with the screwdriver. Like long enough for the power supply to get kicked on.
If you have a voltmeter, you could check for pin 14 (green wire) to go to 0v w/respect to black wires when power should come up. Molex numbering w/latch at the bottom 1-10 top row, left to right, and 11-20 on the bottom, left to right.

Ed Fair
Give the wrong symptoms, get the wrong solutions.
 
Always willing to help if i can. I will do this within the next day or two.
Problem is, its not exactly the same board, but it may help anyway.

Also, its been so long now, have you done the actual bios reset? Take away all power, remove coin battery, move jumper from pin 1 and 2 to pin 2 and 3, leave for 5 min, then put jumper back where it was, put battery back in, then hook up power. Have you done that?



Good advice + great people = tek-tips
 
Edfair and Garebo,

Many thanks and really useful to know. Sounds like the power button is functioning OK and 7-8 pin are definitely power switch.

Have also done actual bios reset twice. Given that it is still not booting it does seem the next step is to try cpu on another mobo (especially now there’s a chance the original (asus) mobo that “died” may now possibly have been a cpu problem after all). With luck I may have tracked down another skt 370 mobo to try the cpu on. Will report back and very many thanks for your continued support.

All the best,
Denis
 
Denis
I just called one person that i know of and he has his computer all apart at the moment. The only connector he has still attached at the moment is the power\on\off, which, as well all pretty much know by now is pins 7 and 8.
He, of course, didnt make a diagram or notation where the other connectors went. His answer was that he would fiddle with them and if he failed he always has me to fix it for him, lol.
I will try another person i know who has this system.

If you have reset the bios a few times, properly, then we have to start looking elsewhere for the culprit.
I also think you might consider starting a whole new thread or post. If you do, then you want to point out you have IBM Netvista, make, model, the cpu info, type of ram, etc, etc, os, what you have tried and where you are right now. But perhaps wait til after you have tested the cpu?


Edfair:
You said "Don't know the interlock timing, but suspect that you need momentary contact with the screwdriver. Like long enough for the power supply to get kicked on"
Same way with these netvistas, same as standard, you just need to hear the power supply go to work and then you take screwdriver away from pins.




Good advice + great people = tek-tips
 
Garebo, Edfair and Rclarke250,

Thank you all for your excellent help. Have now had a chance to carry out following CPU "tests".

a) Tried a couple of different compatible CPUs (P III & Celeron) in Netvista - no change to symptoms.

b) Tried existing CPU in another mobo - appears to work fine.

c) Ram works fine in other mobos.

This suggests Netvista is the problem. Given there is scope to return the board if there are any problems - and given the board is clearly problematic and the extensive efforts already undertaken to find a fix - I have decided it best simply to return it.

I appreciate all your superb help and this might be a bit of a frustrating outcome. The upside is that it has been an excellent learning curve for me and I'm sure advice that has led to fixes for others following the thread. Once again, very many thanks.

All the best,
Denis

 
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