Errors at random times (and how to find help with hardware)

Hello,

I have a machine that was working relatively stable and started throwing some errors at seemingly random times. 
I have not built this machine myself, and unfortunately I don't have access to the person who built it.

After some reading here I think the errors have something to do with the electrical current, but I'm way unprepared to deal with anything electrical. 
The cables on my machine scare me as well. 

I have a couple questions and any help will be great:
- what would be the best way to find someone in Toronto area who can debug this at my workshop and try fixing it?
- what would you say I can attempt on my own?

I didn't have my USB drive with me, so couldn't copy the whole error file. I can probably get one if it's useful. 

What I've tried so far is to go through all the little screws that are keeping the wires tight and tighten them (quite a few of them had more than one and a half spins to get tight. I think they loosened from the vibrations)
I tightened both the wires that cary the power supply and the thinner ones for the computer signals. 
I pressed the tiny signal cables into the driver connector (the one that has a little V-shaped metal that cuts through the cable to make the connection)
I dusted off everything with air in case some metal shaving was stuck in the wrong place.
I got a UPS serge protector in an attempt to ensure stable current (unsuccessful experiment)

When I start the computer and the LinuxCNC app, if I keep everything idle for more than few minutes, without moving any of the axis and without spinning any of the mill or lathe motors, the machine will just throw these errors at some point. 

If I start the mill or lathe motors, then the errors seem to pop up sooner and almost immediately... maybe within 5 seconds most. I've done over 25-30 restarts, and it's the same every time and very consistent. 

Tightening of all the wires and pressing the tiny cables into the V-shaped seems to have changed things slightly, but nothing real. 

 Thank you!

Dimitre

Another annoying after effect is that once these errors pop up, then the "Recycle Machine Power" button stops having an effect, and I need to restart the whole computer in order for the CNC board and the Linux machine to start talking.

Otherwise, if I don't restart the computer but I try to just restart LinuxCNC, the LED lights on the drivers keep staying red.

Previously, when on an occasion I got some error, I was able to just click the "machine power" button, I think it's F2, and then the LED lights would go back to green. 

Hi. You will most likely get better answers than this, but this is what I would check ....

Your config uses a PCI mounted FPGA card inside the PC. From there is a 25pin cable connected to the 7i77 card. Make sure that cable is connected properly. Try removing it and cleaning the ends.

Similarly remove the PCI mounted card and clean the PCI slot and card edge connector.

Henk

Thank you Henk!

What would "cleaning the ends" entail? Is it blowing with compressed air and wiping it with alcohol or something more specialized?

The debug errors indicate that LinuxCNC could not detect the 5I25 card,

Some likely reasons for this are:

PCI slot dirty or 5i25 card not full inserted:
Make sure card is full inserted and secure.
Clean slot and 5I25 fingers with 99% IPA.

Failing ATX power supply, 3.3V rail < 3.1V will prevent the
5I25 from coming out of reset state:
Replace power supply

Thank you! This is great

The power supply is something I neglected to mention in the first post. 
A few weeks ago when it failed for the first time, I observed the green LED light on the power supply flickering. 
So I attempted to replace it with another one, but was not successful and put back the original one, retightened the wires. 
I don't observe the flickering of the green LED any more, but will replace it anyway. 

If the 3.1V is the lower limit that I need to pay attention to, is there an upper limit I need to not exceed? 
Is there a model/brand for power supply that is proven to be better?

Thanks tommylight ! Here is the power supply I currently have. It used to run with this for a year since I have it, but I don't know how long it has run before. I attempted to find a replacement power supply online, but for some reason when I replaced all the cables it didn't even light up... there was no electric power at all. So I just put this old one back, but I want to replace it.

Can you please advise on what power supply would be best to buy?

Thanks much!
 

I did try to clean up the pins on the cable between the PC and the CNC board. It didn't help.

I did open the PC box but I didn't remove the card. It seemed very secure and wasn't looking dirty other than some light dust. 

I did decide to "test" the little screw on the power supply right next to the LED light. I thought it might bring that voltage above the low limit. But that didn't seem to do anything. I tried to put the screw back in original position, but it still only throws errors on start up. Before it used to occasionally start the LinuxCNC application, but now it just gives the error. 

I definitely want to change the power supply. If anyone has an advice for a model, please share a link.

Thank you

Dimitre