USB Ports On The Motherboard For Desktop PCs Do Not Work
Some Capacitors On The Motherboard Are Swollen
Replace Damaged Capacitors
A client contacts me and tells me of a problem on his computer desktop enough blocker: the PC in fact does not allow the use of USB nor those onboard nor available on the PCI card.
The machine has a couple of years, has ASUS motherboard and has recently been updated with a new processor, heat sink with liquid cooling, RAM upgrade and new video card.
However, after some time, the many USB devices attached to it have stopped working .
A quick check showed a very common problem for PC motherboards fixed relative to the electrolytic capacitors that after some time they stop working submitting the rifonfiamenti.
Capacitors Swollen Or Broken Out: That Is The Question
Among the components of the computer more susceptible to heat is the motherboard , often this can present a problem caused by electrolytic capacitors swollen or broken out.
The bulging capacitor can cause several problems to the computer as errors or abnormal behavior, often erroneously attributed to bad hardware or software, because it is not the primary function of filtering capacitor on the supply lines.
A capacitor bulges or bursts when the electrolyte inside it has reached a temperature which evaporate and in this way can leak from the capacitor itself after having caused the swelling, in a form of brownish material.
The capacitor losing the electrolyte gradually loses its ability to become inactive.
The problems with the capacitors on motherboards usually strike the electrolytic filtering of the supply lines as a result of strong currents that must manage during operation of the computer these elements are subject to high overheating.
This article describes how to replace some electrolytic capacitors having this problem in a motherboard.
Before you start trying to analyze each capacitor to be replaced: I jot down as technical capacity, maximum operating temperature (usually 85 or 105 ° C).
These data on electrolytic capacitors are easy to find right on the capacitor.
Then we have two roads to get capacitors functioning: buy in specialty stores new capacitors with voltage, capacity and operating temperature equal to or slightly above the capacitors to be replaced by ensuring that they have a low value of ESR (equivalent resistance), which is suitable to filter the high frequencies Spurious present in the power lines of the computer or look for them on old motherboards is.
Obviously in this case we must proceed to unbrazed trying not to damage them.
Personally I purchase regular moderate amounts of electrolytic capacitors for motherboards of PCs and tantalum capacitors used mainly in notebook; I choose the most common types and capabilities.
In my case the capacitors that showed swelling were very many, at least ten, and were formed 6.3 volts and capacity 820 uF ; I used to replace these electrolytic capacitors slightly more capable and that is from 6.3 volts and capacity 1000 uF .
There was also another capacitor to 25 volts and 470 uF , whose substitute I found on an old motherboard.
The location was quite swollen capacitors indicative: near the PCI port , adjacent to the USB ports onboard and close to the USB connectors of the front doors .
In fact, the PC complained, as it happens, the problems in these areas.
First seek the pin positions of the various capacitors to replace the other side of the card (it is understood that this procedure applies only with capacitors mounted by pin and surface / SMD).
Some Wick these components using hot air stations : personally I prefer the classic soldering iron , possibly quite powerful (60 Watt) and a tip top condition.
It should also tin high uninviting , a blower tirastagno and the flux or solder paste .
Dissaldiamo so old capacitors and risaldiamo new , then we cut the part of the pin in excess and we clean the motherboard with an appropriate solution.
After soldering you make a control board to make sure that there are no burrs in the solder.
Then reassemble the whole thing and, in this case, I’m very careful to sink with liquid cooling of the Cooler Master.
After installing all the computer text and .. tuttok !!
The replacement of the capacitors solved the problem there was with the USB ports! Now all external devices, including hard drives USB 2.5 (which require a lot of power) do not give any malfunction.