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Thread ID: 113844	2010-11-06 18:20:00	Bulging Caps on Motherboard	Myth (110)	Press F1

Post ID	Timestamp	Content	User
1150775	2010-11-06 18:20:00	Morning, have a motherboard here (Gigabyte K8VM800M) with one cap that is reasonably advanced in its bulging - but hasnt split yet. It is located right by the RAM modules and close to AGP slot. Am looking to replace this, but having never done this before; am wanting any advice you all have to offer. I have read elsewhere in this forum that the capacitor must have the same value or higher; but is there any other advice I need to know. Am ok at soldering - just have never touched motherboard before, and haven't touched a PCB in years. Best place to buy these - Jaycar/Dick Smith/Other? Any advice on the actual soldering? All the other capacitors look fine, not even a slight hint of a bulge on any of them. Motherboard still working fine, but the owner wants a backup, and complete re-install for long-term use.	Myth (110)
1150776	2010-11-06 20:25:00	As you say, you need more or less the same capacity, and voltage rating the same or higher, and of course physical size is probably fairly critical. Ideally, the capacitor would be a low ESR type, but a 105 degree C one should be ok. I would use solder wick to remove the old cap. What is the capacity and voltage? Are you handy to a shop? Jaycar would be better than DSE, I reckon.	rumpty (2863)
1150777	2010-11-06 20:32:00	Just done some on Gigabyte board and had problems getting the right values ... may have a couple spare if you have the same problem as I had to but 5 at a time. Let me know the values.	SP8's (9836)
1150778	2010-11-06 22:37:00	Capacitor values are: 3300μF 6.3V	Myth (110)
1150779	2010-11-06 23:11:00	See if you can buy them locally .... think I only have 1 of those left. I replaced all 4 on the mobo plus another 3 - 1500uF @ ,16v. When they start going I prefer to replace all rather than just the one that looks crook on the top ... often they start bulging from the bottom and you can't see it.	SP8's (9836)
1150780	2010-11-07 07:20:00	I use Jaycar. As already said, get the 105 degree low ESR types if you can. Jaycar have a fairly limited number of caps in the 6.3v line, and from memory, I doubt they have the 3300uF. Just checked, and in the low ESR they have none in 6.3v. Nearest is: CAPACITOR ELECTROLYTIC 4700UF 10V 105C L/ESR, which will probably be ok. This one needs a higher voltage (10V) in order to get the even higher capacitance (4700uF), so at the lower supply voltage of 6.3v it should end up with a lower capacitance, approaching the 3300 that you want. Biggest problem may be its physical size - you might struggle to fit it between existing mobo components. You don't necessarily have to mount it flush with the mobo however, it can be left on it's long legs, giving the potential to nudge it out of the way of other bits. However - long legs increase the chance of inadvertently shorting the legs together, or against other components, in which case some heat shrink on the legs may help. My own experience replacing caps: Monitor mobo - easy, large holes to accept the 'legs', and consequently easy to insert. Computer mobo - much smaller holes, much more difficulty getting the cap all the way down onto the board, and much finer soldering spots required (and more to damage with the soldering iron). Make sure you don't get confused which hole takes the negative terminal. The pros recommend removing all static sensitive components first, so that means the RAM and CPU, and the need to put new thermal compound on the CPU when you put it all together again. Give the CPU heat sink some gentle twists / side to side motion to loosen it up before trying to lift it off, as in some cases the thermal compound can be fairly dried out, and damage to the CPU can occur if just yanking off the heatsink.	Paul.Cov (425)
1150781	2010-11-24 18:48:00	Ok, bought some caps from Jaycar yesterday (3300μF 6.3V low ESR @ $3 per cap). Replaced it last night, and then rebuilt PC this morning. Boots up - which is always a good start. Now, how do I know if this fix was done proper - i.e Im not going to get random issues all of a sudden. Is it worth load testing the mobo - would memtest do this (considering the cap was right by the RAM modules)? Any other app better?	Myth (110)
1150782	2010-11-24 23:51:00	The Jaycar Low ESR caps Ive bought are rubbish - but usable They arnt really low ESR, I measured them with a ESR meter. Hardest part is getting the old caps out without damaging the m/b What Ive tried is cut the cap in 1/2 , pull the 'body' off leaving 2 wires to easily solder the new cap to. Chances are there will be MANY bad caps on that m/b, not just the obvious ones you replaced. The repaired mb may keep working for years, it may re-fault tommorow. I wouldnt trust it as a serious/work PC.	1101 (13337)
1150783	2010-11-25 00:02:00	Yeah, the ones from Jaycar are pretty bad. If they are Samxon they may be OK but if they are Suntan they are junk. What you want is something like Panasonic, Rubycon or Nichicon etc. These can be bought from RS-Components at a better price than Jaycar usually (and with free shipping) Normally you should use the same value capacitor. You can use higher voltage if you can't find any of the original voltage. New ones should have ESR the same or lower than that of the originals. New ones should have Ripple current same or higher than that of the originals. You need to get the originals, and find the brand and series (usually printed on them) - then download the datasheet for them to find ESR and Ripple specifications. Then compare these to capacitors for sale at RS and find ones which are the same or better. Always use 105 Degree rated ones too. For a guide on how to do the desoldering etc, look here: www.badcaps.net	Agent_24 (57)
1150784	2010-11-25 00:18:00	Chances are there will be MANY bad caps on that m/b, not just the obvious ones you replaced. The repaired mb may keep working for years, it may re-fault tommorow. I wouldnt trust it as a serious/work PC. I'd just like to add that some caps will start bulging from the bottom before being noticeable on top. As my previous post said, I had several bulging and replaced a total of seven just to be on the safe side ... all worked out OK once replaced.	SP8's (9836)
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