Nvidia 790i Ultra Bad Caps Causing Problems?

[momaka]

Most MCZ (and MFZ) I found on eBay were genuine, but rather old stock.
The 6.3V ones may indeed be a bit "unstable", especially used ones pulled from old boards, and also if they have sat unused for very long... at least that's my personal experience.

MBZ, on the other hand, seem to hold up OK. Haven't had issues with any yet.

That said, Panasonic FR, FM, and FS along with UCC KZH and KZM and Nichicon NV/HW can often be "good enough" for most motherboard use cases.

[stj]

MBZ / MCZ have not been made for many years now,
any for sale are fake or ancient

[diabedon]

I wouldn't really recommend MCZ as they have unstable electrolyte like KZG and typically don't last very long. Some short out without signs of damage, but I haven't experienced that, just very vivid deaths.

[hsdb]

Hello,

Purchased a 790i Ultra, the seller replaced 4 caps with new ones and possibly higher values and now the board won't fit long GPUs anymore in slot one, original values unknown. Can anyone help identifying voltage and capacitance of the four highlighted in red below?

The caps in question are:

C4J12, C4J13, C5J3 C5K2 located immediately behind the floppy connector.

Thanks in advance.

[mikay786]

Re: Nvidia 790i Ultra Bad Caps Causing Problems?

Cheers, ordered 15 from badcaps last night, thought id order a few extra as this seems like a common problem with these boards.

[c_hegge]

Re: Nvidia 790i Ultra Bad Caps Causing Problems?

Anything in the UK you can recommend?

RS Online has a UK branch too.

http://m.rs-online.com/h5/mobile/uk/...um-capacitors/

The appropriate capacitor series are all discontinued now. RS and element14 will have all sold out long ago. badcaps.net is about the only one that still has stock of them, as Topcat did a massive bulk order shortly before they were discontinued (and yes, badcpas.net does ship to the UK).

HOWEVER

There are a few series which are not ideal replacements but might just be close enough. Panasonic FM series is probably the closest in terms of electrical specifications, but, like the Ruby ZL you were considering earlier, it is physically a few mm larger in diameter, so you may have a hard time squeezing some of them in.

Since the caps in question do appear to be used for VRM filtering, you could probably poly-mod the board using lower capacitance (like 820uF) solid caps such as Nichicon FPCAP L8, which are the correct diameter. I've had pretty good luck poly modding motherboards in the past like this, but be warned that it is experimental and I don't by any means guarantee that it will work.

[ReeceyBurger123]

Re: Nvidia 790i Ultra Bad Caps Causing Problems?

Hi, Yes replaced them yesterday and have not had a crash since.

Big thanks to all you guys for the advice and help, that's two things fixed now thanks to this board!

Good to here, enjoy your system

[mikay786]

Re: Nvidia 790i Ultra Bad Caps Causing Problems?

Anything in the UK you can recommend?

RS Online has a UK branch too.

http://m.rs-online.com/h5/mobile/uk/...um-capacitors/

[c_hegge]

Re: Nvidia 790i Ultra Bad Caps Causing Problems?

^
Rubycon ZL? No. They are too high ESR. Farnell do not have anything suitable for this application (although a panny FM might just be close enough if you can squeeze a physically larger cap in). Use https://www.badcaps.net/store/produc...products_id=39 from badcaps.net

[mikay786]

Re: Nvidia 790i Ultra Bad Caps Causing Problems?

http://uk.farnell.com/jsp/search/pro...sp?sku=1144672

As above will these caps do?

[RJARRRPCGP]

Re: Nvidia 790i Ultra Bad Caps Causing Problems?

Also, higher RAM voltage means higher thermal dissipation for the chips on the RAM, hence shorter lifespan for the RAM - especially for the cheaper brands.

1.9 V is unlikely to damage DDR 2.

High failure rates are mostly with 2.0+ VDIMM and with DDR 2 Micron D9s.

[RJARRRPCGP]

Re: Nvidia 790i Ultra Bad Caps Causing Problems?

I would not recommend increasing the voltage unless recapping doesn't help. I think you're board only plays up because it's an ASUS and probably has a cheapped out VRM.

I didn't mean that. I assume that the board is to be recapped first before making voltage adjustments.

[mikay786]

Re: Nvidia 790i Ultra Bad Caps Causing Problems?

http://uk.farnell.com/jsp/search/pro...sp?sku=1144672

RUBYCON - 6.3ZL1500MEFC10X20 - CAP, ALU ELEC, 1500UF, 6.3V, RAD (ZL Series)

guys would the above be suitable as a replacement to the Sanyos?

Ive got another board with the exact same caps leaking on them cant be arsed waiting 2 weeks for the MCZ from eBay China, these are local to me so can pick up. Well anything from Farnell will do as is local to me.

[mikay786]

Re: Nvidia 790i Ultra Bad Caps Causing Problems?

Did you end up replacing them, if so did it fix the problem ?

Hi, Yes replaced them yesterday and have not had a crash since.

Big thanks to all you guys for the advice and help, that's two things fixed now thanks to this board!

[ReeceyBurger123]

Re: Nvidia 790i Ultra Bad Caps Causing Problems?

Did you end up replacing them, if so did it fix the problem ?

[mikay786]

Re: Nvidia 790i Ultra Bad Caps Causing Problems?

Should I replace all 5 of the Sanyos? 1 of them seems ok but since I have ordered 5 Rubycon and there are 5 Sanyo caps?

Also after reading around 1.5v seems quite low for DDR3 boards back say 2008 when the 790i came out. Ive read a few places saying low voltage stuff can cause issues on the 790i and to bump up the Ram volatges especially when using 4 sticks.

I bought the system second hand for not much money and unfortunately reset the CMOS so didn't get a look at the voltages set for the RAM (although since they are the original sticks you would imagine dell would have programmed that into the bios)

Noticed the caps had discharge on them so stripped the system, completely forgot about trying to up the voltages on the RAM but I guess this needed doing anyhow.

Will see anyhow once new caps arrive.

[c_hegge]

Re: Nvidia 790i Ultra Bad Caps Causing Problems?

Sounds like maybe undervolting, and with 4 sticks, I would bump it to 1.65 V. Sounds like it may be acting up like DDR 2 does.

I would not recommend increasing the voltage unless recapping doesn't help. I think you're board only plays up because it's an ASUS and probably has a cheapped out VRM.

[Wester547]

Re: Nvidia 790i Ultra Bad Caps Causing Problems?

Sanyo WG capacitors are actually very pristine as far as their known track records go, I haven't heard or seen any fail other than from discolorating levels of heat. It's Sanyo WF that's known to fail and that's what the OP's board has. I'd say those were indeed causing the issues in question, but I wouldn't say the power supply is quite built like a tank... it does look like a very nice Hipro save for the CapXon HP primaries which in the application of APFC will eventually fail so those should be taken care of too.

[RJARRRPCGP]

Re: Nvidia 790i Ultra Bad Caps Causing Problems?

Ram is rated at 1.5v according to the label, although I have read this board does throw fits with lower voltage stuff. (although this is the RAM supplied by DELL in the XPS 730)

Sounds like maybe undervolting, and with 4 sticks, I would bump it to 1.65 V. Sounds like it may be acting up like DDR 2 does.

[theokretes]

Re: Nvidia 790i Ultra Bad Caps Causing Problems?

Those caps on amazon are very very very likely FAKE. Do NOT use them in anything you care about! Chances are, they will not last long at all and you will need to recap the board again (or worse, they could go so bad that they could kill a MOSFET).

Actually, those Sanyo's that are originally on his board right now could well be genuine. IIRC, it was mentioned on badcaps a few times that WG series aren't very stable.

Yeah that's something that always irritated me. There's a lot of counterfeit products sold on amazon that sellers complain about stating 'this is not a good brand', but it's not the brand but the counterfeit product...

I actually think those are genuine sanyos. The covers have the faded printing that you see on genuine ones. And OEMs typically have sources to genuine parts.
--> it seems like there's a lot of blame for OEMs using fake capacitors, when this is simply not the case