identifying SMD ceramic capacitor damage

[Proxyep]

I have a few graphics cards (not working) on which the SMD ceramic capacitors appear to be different colors.
The are mainly brown (like normal SMD ceramic capacitor brown) but others are a dark grey! Thing is on the exact same motherboard revision but another different board the exact same capacitor can be a different color

Long story short but does the dark grey mean that it has overheated/burnt?

[PeteS in CA]

Re: identifying SMD ceramic capacitor damage

I've seen brown/tan SMT ceramic capacitors, I've seen grey SMT ceramic capacitors, I've seen white SMT ceramic capacitors ... unused and in bags or on auto-insert tape. When SMT ceramic capacitors short or get leaky, they aren't subtle. They make loud noises, glow brightly and often damage the PCB. Large form-factor SMT monolythic ceramic capacitors are evil, but frustratingly necessary (try finding a 2uF, 600V electrolytic or film capacitor that is just 1 cubic inch in size!).

So, no, the grey color is not, of itself, a sign that the cap has overheated.

[b700029]

Re: identifying SMD ceramic capacitor damage

As their name suggests, they're made of ceramic. They're fired in a kiln, and the color variation may be dependent on insignificant factors such as how long they were in there for, and small differences in the composition of the ceramic. It's nothing to worry about.

[aurgathor]

Re: identifying SMD ceramic capacitor damage

SMD ceramics themselves are fairly reliable, but if they do fail because of spikes or overvoltage, chances are good that something else got fried, too. When they do fail w/o overvoltage, that's often physical because of stress levels, or the failure is caused by other external factors, often related to soldering, etc.

You could probably test them with a good capacitor tester, but I think the fault lies elsewhere.

[kc8adu]

Re: identifying SMD ceramic capacitor damage

some of those are inductors too.