Forum latest

Guide: Replacing capacitors in the EPoX 8RDA+ - Page 3
Written by Gizmo   
Sunday, 12 June 2005 15:27
Article Index
Guide: Replacing capacitors in the EPoX 8RDA+
Page 2
Page 3
Page 4
All Pages


A Word About Static


I know many people are of the opinion that if you didn't feel the shock, there wasn't a static discharge.  Well guess what folks.  YOU'RE WRONG!  Just because you didn't feel it doesn't mean it didn't happen.  The average human cannot feel a static discharge of less than five thousand volts unless it hits a really sensitive part of the body.  Most components can be damaged by discharges of as low as one thousand volts.

I've also heard statements like "I've worked with electronics for YEARS and never worried about static-free stations or wrist straps.  It never caused ME any problems."  Well, I'll say that it did, but you didn't know it.  A part that is damaged by ESD (electro-static discharge) may not appear to fail right away.  In fact, it may appear to work just fine for a while.  However, it is quite likely that component will suffer a premature failure due to the ESD event that didn't happen because you "didn't feel it".

Static mats and wrist straps can be purchased at any reputable electronics store.  In a pinch, you can make a mat using a piece of cardboard covered with foil and attached by a wire through a one megaohm resistor to a ground (the ground prong in your electrical outlet; just be sure it's grounded.  A water pipe or electrical conduit usually also will work).  A wrist strap can be made using foil wrapped around wrapped around your wrist, and also attached via a wire through a one megaohm resistor to ground.  Even a watch band or bracelet can be used, so long as it is metalic.  In short, don't give excuses for not having a grounded static-free work area.  For the cost of some aluminum foil and your time, you can make one.


Are we there, yet?


Finally, we get to the actual work.  First, you need the board, and you need to identify the components to be replaced.  Generally, only the parts around the VCore regulator will actualy be 'blown' but as long as we are doing this, we might as well get all the likely culprits.  In this picture, I have circled all of the parts we will be replacing:

View a larger version of the image

The rest of this is pretty straight-forward grunt work.  Pull a part out, find the matching capacitance and voltage among your spares, put it back in and solder it in place.  Be very careful, though!  Most electrolytic capacitors have a polarity.  They will generally be marked with a colored band that runs from the top to the bottom of the cylinder, and that band will have a big '-' symbol printed every so often inside it.  This is the negative voltage side of the capacitor.  If you don't see the band, then the capacitors will also have one lead that is shorter than the other.  This short lead is the negative voltage side of the capacitor.  When you remove the old part from the board, pay special attention to how it is marked and oriented.  It should be marked in the same fashion, and you need to make sure that you put the new part in with the same orientation as the old part.  If you should happen to pull the part out and forget how it goes back, don't despair.  The board will also be marked with a '+' sign on one hole and a '-' sign on the other hole, indicating which orientation the capacitor should be placed in when it is inserted.  Just make sure you get the caps in correctly.  They won't live long if you don't.  :(

Don't Click Here Don't Click Here Either