Bad contacts problem. How you deal with it?

[goodpsusearch]

So, you have all faced at some point instability problems caused by bad contacts, or the part not recognized at all (for example a RAM DIMM, or a PCI card, or GPU).

What would you do? Would you clean the contacts and if yes, what cleaner you use?

I have a customer's desktop PC which randomly crashes. I thought the problem was the 9500 geforce and ordered a new Graphics card. Now there is problem with the PCI LAN card disconnecting because I had to change the PCI slot it was installed. Also the RAM looses electrical contact with the system if the case is moved.

What can I do? Please help

[SteveNielsen]

Re: Bad contacts problem. How you deal with it?

I would blow out the slots with air and clean the card edge contacts with a pencil eraser.

[c_hegge]

Re: Bad contacts problem. How you deal with it?

My rule of thumb is that if I have to re-seat the RAM or cards more than once a year, then they just get replaced.

[goodpsusearch]

Re: Bad contacts problem. How you deal with it?

the cards / ram or mobo?

[dj_ricoh]

Re: Bad contacts problem. How you deal with it?

IPA and a brush

[dj_ricoh]

Re: Bad contacts problem. How you deal with it?

if you want real hard core wash take in the shower liquid detergent and wash it .

dry with hair dryer(needs to be uniform)

or oven it for a couple of minutes under 100c

[goodpsusearch]

Re: Bad contacts problem. How you deal with it?

https://www.crcindustries.com/ei/pro....aspx?id=05101

Is this what I need?

[modman1337]

Re: Bad contacts problem. How you deal with it?

U'd be wasting your money on that stuff as suggested get yourself a rubber I use Staedtler Mars Plastic Eraser, then some IPA on a cotton bud and rub down to make sure and ur good to go.
The IPA has so many uses, I clean screens and keyboards with it also.

[goodpsusearch]

Re: Bad contacts problem. How you deal with it?

But how to rub slots?

[mariushm]

Re: Bad contacts problem. How you deal with it?

Isopropyl alcohol and a soft toothbrush (preferably with natural pig hair) or some good paper towel.

Get the towel damp with isopropyl alcohol, fold it in two then rub the memory stick pins on the wet towel, to clean the contacts.

As for memory slots, a trick I've learned is to get copier machine paper, fold a page once or twice to get a suitable thickness then gently slide it through the memory slot. The surface of the copier paper will act like fine grit sanding paper, rubbing away the more difficult to remove oxidation from the pins without bending them too much or damaging them.

After a few passes, you can wet the toothbrush in isopropil alcohol and do the same as you did with the copier paper, call it a "finesse" pass, to remove whatever's lest on the pins.

[clearchris]

Re: Bad contacts problem. How you deal with it?

If I thought the problem was the card was worn and not the slot, I'd consider tinning the contacts. I'd use a super thin coat, just enough to change the color. I'd probably not do both sides one should be sufficient.

Might be worth a shot if you are going to throw the card out anyway.

[Agent24]

Re: Bad contacts problem. How you deal with it?

I'm not sure that tinning the contacts would be smart. Solder oxidises more easily than gold or other plated conductors, which is why gold etc is used. You might fix the problem for a short while, but it would likely come back again sooner rather than later.

There are re-plating kits with fibreglass brushes and special plating pens that you can use to repair worn\damaged contacts, but that only makes sense if the card is worth more than the kit.

[momaka]

Re: Bad contacts problem. How you deal with it?

I would blow out the slots with air and clean the card edge contacts with a pencil eraser.

+1 for the pencil eraser. I've used that method to clean RAM connectors, and it worked great. Haven't gotten any flakiness from the computer that I tried it on since.

Now, if the PC has been working in a grimy environment, you should also consider giving it a wash with dish or other, non-chlorine detergent. I had a dirty SCA HDD that refused to show up in BIOS and work with the PC, even though it did spin up and initialize okay. Tried connecting and disconnecting multiple times to rule out a bad connection. Eventually, I gave the PCB a good cleaning and wiped all of the contacts with a pencil eraser. Result: HDD working again.

[goodpsusearch]

Re: Bad contacts problem. How you deal with it?

I was so sceptical about the pencil eraser trick but oddly it works


I also ordered that:

http://www.you.gr/proionta/frontida-...lean-crc-200ml

I didn't find it so expensive and I thought let's try it out. Do you think it's not good enough?


One last question. Do you know how to find isopropyl alcohol at a reasonable price?

I asked some pharmacies and they ask 18euros for 1litre!

Should I order it from ebay? Is it safe or I may end up getting chinese water?

[Agent24]

Re: Bad contacts problem. How you deal with it?

One last question. Do you know how to find isopropyl alcohol at a reasonable price?

I asked some pharmacies and they ask 18euros for 1litre!

Compared to here it's not too bad. There's only one shop you can buy it from around here which is $20 for 1 litre. Your one works out to $31 in NZD. 1 litre lasted me a couple of years for hobby use so I think it was a good price really.

You'd probably have to go to some industrial supply company if you wanted it cheaper.

eBay might be cheap but liquid is heavy, and I bet you the Chinese stuff would have something wrong with it.

[mariushm]

Re: Bad contacts problem. How you deal with it?

I bought a half liter bottle of 99.7% purity for about 5$ here.

I can understand it could be expensive to get in Greece as it's hard to ship due to its flammability but it should still be easier to find in chemical stores or electronics store.

Pharmacies should have rubbing alcohol but that usually only has about 70% isopropyl alcohol and the rest is water and perfume and sometimes other crap that could remain on boards after the alcohol evaporates. For electronics use it's best to use 97% of better purity, ideally 99.5% of better.

[clearchris]

Re: Bad contacts problem. How you deal with it?

I use brake cleaner , 3.50 for a big can. Downside is it will melt some plastics. Dont solder around it either, when it burns it creates some very nasty gasses.

[rievax_60]

Re: Bad contacts problem. How you deal with it?

I have been using PAO synthetic oil on all sorts of contacts and pots for 15 years with good results. It is available as synthetic aircon or air compressor oils.
It is the only stuff that gave a long term fix for the wafer switches in my old audio amp.
I also do clean PC main boards by full immersion in rain water. It is a bit of a worry trying decide when it is properly dry.

[redwire]

Re: Bad contacts problem. How you deal with it?

For dirty, oxidized contacts I use a piece of paper like a piece of sandpaper. Gently rub the piece, or on a business card, against the contacts.
The fibres are abrasive enough to clean off dirt, but not harsh to scrape off contact plating (gold etc.)

[rhomanski]

Re: Bad contacts problem. How you deal with it?

This works best for me. Comes in a variety of containers and applicators. I have several switches I cleaned with it 5 years ago and haven't had to clean them since.