Operational Bad Caps?

[Kong]

What kind of chance does a motherboard with a few blown capacitors have at operating normally for an extended period of time? I understand the chance probably isn't that great, but has anyone ever had a computer that had some bad caps which were left alone?

I have a computer with a motherboard (MSI K8N Neo4-F) that has some blown capacitors around the CPU region, and they've been that way for a couple years. Although, I've mostly had the computer turned off since I discovered the bad caps. It can still be turned on and it seems to run ok, but I don't want to keep it on 24/7 under such circumstances.

I'd like to fix the bad caps but all I've got is a basic Radio Shack pen iron and probably not the right kind of solder. Can motherboard caps be replaced with such equipment?

[Uranium-235]

Re: Operational Bad Caps?

yeah it can. it helps with better equipment but i've replaced them before with sucky irons in my first days, just be careful

continuing with bad caps can damage other parts, but I have seen things with bad caps continue working

[Raul]

Re: Operational Bad Caps?

I found a Dell 8400 at the city dump and after ordering parts for it, got it working great after two days of fixing problems, the next day it died at start up and the caps still looked the same, bulging slightly but none burst open. So the computer may last a long time or die at any moment.

I am going to replace the caps with just a cheap soldering iron, it should not be a problem if you don't overheat the leads.

Someone suggested pulling the caps with pliers and then desoldering the leads while pulling them, I will go that route since I already tried the technique of heating one leg at a time while pulling the capacitor (I replaced the caps in a video card and I had to heat the capacitor leads far longer than I felt comfortable).

[Uranium-235]

Re: Operational Bad Caps?

sometimes if you have a board with cheapass solder it will pull the leads out of the cap cause the solder will just not liquify enough to do a successful pull

this is where flux helps. On the board i'm fixing, I wet each joint with flux and apply some good leaded solder to the point where the solder changes to more glossy texture. then I use a desoldering tool and do a clean pull, to where each joint has a clean hole

if you don't have a desoldering tool, just apply flux, and good solder, then walk it out, it should be alot easier then just heating the joint dry

[dood]

Re: Operational Bad Caps?

I always add a bit of fresh solder to the joint before I try to walk the cap out. Makes it a much easier job. Also, a lot of Dells utilise large grounding planes, so they may need more heat to get the job done. This is where an adjustable iron comes in handy. On a scale of 1-5, I usually keep the iron at 3, unless I'm working with large ground planes, then I bump it up to 4. Those are scientific measurements, too

[Kong]

Re: Operational Bad Caps?

Is there a single type of solder that works well with most motherboards?

Also, is it necessary to remove the CPU from it's socket before replacing caps?

[Th3_uN1Qu3]

Re: Operational Bad Caps?

Just use regular 60/40 solder. Removing the CPU isn't mandatory but it's a really good idea to do so.

[Kong]

Re: Operational Bad Caps?

Cool, thanks for the tips, everyone.