406coupe.net

The other day, I found a Dell PC thrown away near the junk box when I came back from a meeting. It was Optiplex GX270. Memory modules and HDDs were already taken away, though the CPU still remained. I detached the CPU and remove thermal conductive material, then letters "3.20GHZ/512/800" came out. It's a Northwood!

I found and asked the person who threw the PC away why. He ,my younger colleague, said it sometimes hung up at the BIOS screen. I would know the reason soon. There were quite a lot of bulging capacitors on the motherboard.

On the Internet, GX270 is well-known with its bulging capacitors. Dell is trying to replace its motherboard. Of course some of our colleagues know about that. Though they say this motherboard's serial number wasn't on the list of this replacement program.

Bad capacitors looked made by "Nichicon"(HN Series). 5 of 5 6.3V 1500uFs and 1 of 3 16V 1800uFs were bulging. A shop selling the same capacitors in Akihabara "San-ei Denpa" was found easily. I went to get them and replaced all bad capacitors. Finally the PC began to work properly again.

But... I'm still not sure why Nichicon capacitors made this bad problem. Nichicon is a manufacturer who has been producing good quality caps for more than 50years. A few years ago, there were so many bulging capacitor troubles on various motherboards. After that almost all motherboard manufacturers changed their capacitors from Chinese brands to Japanese ones.

However, the motherboard was assembled in China. So most components could be provided from Chinese suppliers. Nichicon caps too. This is just my guess...
Are these Nichicon caps "Fake"? Please see this picture. Upper one is a bad cap I removed and lower one is a new cap I bought. You can see the difference between them. The logo "nichicon" on upper one is quite bad and the font of some letters look different. Can you believe they were made under the same quality control standards?

Any way, I replaced bad caps with the same spec Nichicon caps. I should continue watching this repaired PC.

Shop keeper of San-ei Denpa had the same opinion as mine. He said he've never seen this bad Logos. And he recommended new HZ capacitors would come soon than HNs. Though I could not wait. It's OK! I could replace capacitors easily.