Dell Dimension 4700C - V-Core Rubycon MCZ's were ALL bad

[PCBONEZ]

Re: Dell Dimension 4700C - V-Core Rubycon MCZ's were ALL bad

Granted I missed HZ 'cause I don't buy them and they don't have that many sizes but.....

And AFAIK all Mouser carries in lytics with better specs than FM is Nichicon HN and HM.

Mouser dropped HM and HN when they were found defective until it was clear the problem was fixed.
Started carrying them again in '08 or '09 I think.

[bw1]

Re: Dell Dimension 4700C - V-Core Rubycon MCZ's were ALL bad

Well I've got more than enough of these in stock, which by the sound of it would work for the 8 v-core. Also, I do want to use 8 now, not 5, correct?

Still not sure what to do with the oddball... would this work? Ripple is good and impedance is 9 vs. original 12.

*I'm calling it an oddball because it's the odd one out in this case, not because I think it's a strange cap/value in general.

[PCBONEZ]

Re: Dell Dimension 4700C - V-Core Rubycon MCZ's were ALL bad

Well I've got more than enough of these in stock, which by the sound of it would work for the 8 v-core. Also, I do want to use 8 now, not 5, correct?

You can go either way but using 5 @1500 will probably cost more.
If you go with 5 then make sure to spread them out in Vcore.

Still not sure what to do with the oddball... would this work? Ripple is good and impedance is 9 vs. original 12.

The % difference makes it seem like a lot but the values are so low to start with it only amounts to a .003 ohms change.
- Should be fine.
[Where it's positioned right next to the 2x2 PSU connector make sure you didn't error and it was actually a 16v cap.]

*I'm calling it an oddball because it's the odd one out in this case, not because I think it's a strange cap/value in general.

Me too.
.

[bw1]

Re: Dell Dimension 4700C - V-Core Rubycon MCZ's were ALL bad

Where it's positioned right next to the 2x2 PSU connector make sure you didn't error and it was actually a 16v cap.

Yeah I double checked already earlier - I've got (9) 6.3's here from it.

[bw1]

Re: Dell Dimension 4700C - V-Core Rubycon MCZ's were ALL bad

UPDATE: Used the (8) 820uf poly's I already had and used a Samxon GC temporarily next to the 2x2 12v to test it out and it worked for a quick power up test.

I did discover that the power supply (stupid micro/mini narrow custom thing for these slim computers) was bad as well though, so my successful test was using a new power supply. I should have caught that, but the caps were so bad it didn't even occur to me to check the power supply.

I'm sure that was the reason it wasn't turning on as of recently, but I have no idea how it was running up until that point, because 7 of the 8 v-core caps had a good amount of dried up electrolyte stuck to the tops of them.

[PCBONEZ]

Re: Dell Dimension 4700C - V-Core Rubycon MCZ's were ALL bad

If the uF is appropriate the Samxon GC can be a permanent fix.

[bw1]

Re: Dell Dimension 4700C - V-Core Rubycon MCZ's were ALL bad

The voltage, uF, and impedance are correct, but the ripple is under the original.

2220 vs. 2350

Or is that close enough?

[PCBONEZ]

Re: Dell Dimension 4700C - V-Core Rubycon MCZ's were ALL bad

I could be wrong but,,,
I would normally expect to see something like an MBZ in that position and I suspect the only reason they used MCZ is because they had to stock them for the VRM anyway.
In other words I think they used an over-spec'ed cap in aid of simplicity at the factory.
[That and MBZ may have already been out of production when it was built.]
.
[Back to.] I would normally expect to see something like an MBZ in that position and an MBZ's ripple would be ~2000 so I think the GC will do just fine.
.
.
.
On the Dell/Intel boards when MBZ and MCZ were both readily available it was common to see MCZ [or HN] in Vcore and MBZ [grade] every where else on the board.
Just after MBZ went 'poof' a lot of Dell boards started using MCZ where MBZ used to be.
I think that's the case here.
.

[bw1]

Re: Dell Dimension 4700C - V-Core Rubycon MCZ's were ALL bad

Very good points - Thanks!

[bw1]

Re: Dell Dimension 4700C - V-Core Rubycon MCZ's were ALL bad

UPDATE: Replaced the V-core (Low) w/the (8) 820uf polymers. Also replaced the (4) V-core (High) with Samxon GC's. These looked just fine, but were '04 HN's, so I didn't trust them.

At first power-up attempt, got nothing. Tested power supply and it was bad. Replaced it and everything working. Yes, I probably could have tracked that problem down too, but replacements aren't horrible, and the thing is really cramped and overall a PITA to work on.

I suppose it's possible that the only "problem" when it came in was the power supply, but as bad as the V-core (Low)'s were leaking all over, it's amazing it was running as long as it did and it didn't even cross my mind to check the power supply first.

Overall seems like a bit much work for the computer it is, but everything has been working great for a day now, so looks like it's good to go.

Thanks everyone!

[Tesla]

Re: Dell Dimension 4700C - V-Core Rubycon MCZ's were ALL bad

Also, check that the 4 solder connections (for 2 loops) that hold down the NorthBridge passive Heat-Sink are soldered in good.

My father-in-law has a Dell 4600c. The other day, I found that one loop got so hot it un-soldered itself and the HS fell off. It also completes a circuit, so the BIOS complained about HS Failure. The one that was still in there looked like a cold solder, so I also removed and resoldered that one as well.

It had a pad (instead of paste) and it looked fine, so I just re-used it.

Works fine now.

[PCBONEZ]

Re: Dell Dimension 4700C - V-Core Rubycon MCZ's were ALL bad

These looked just fine, but were '04 HN's, so I didn't trust them.

Good call, and Congrats!
.

[TCKTMB]

Re: Dell Dimension 4700C - V-Core Rubycon MCZ's were ALL bad

Also, check that the 4 solder connections (for 2 loops) that hold down the NorthBridge passive Heat-Sink are soldered in good.

My father-in-law has a Dell 4600c. The other day, I found that one loop got so hot it un-soldered itself and the HS fell off. It also completes a circuit, so the BIOS complained about HS Failure. The one that was still in there looked like a cold solder, so I also removed and resoldered that one as well.

It had a pad (instead of paste) and it looked fine, so I just re-used it.

Works fine now.

The old familiar PINGGGGGG, those clips fly off SX280s too.