Corsair HX620

[Madcat]

Yay! Insomnia! *cough*

Simply put, if I should play a demanding game, or leave my pc to idle for hours....POOF system is down. The first time this ever happened, my system would power cycle with "ON" being less than one second. The system would power cycle reasonably fast, so I pulled the plug quick. Now the system would shut down suddenly, but I can power it back up. First three things come to mind: either thermistor is brainfarting, some components are actually breaking down, or the fan was too damn slow. What sucks is I already have this guy disassembled right in front of me for about two weeks. My initial reaction was knee-jerk as I assumed dying lytics. I'm starting to wonder if the mobo could be going. I DID have an overclock going from 2.5ghz stock to 3.0ghz. Heat wasnt an issue since my temps were all good. I'm guessing all the residual heat in the case mustve gotten to the PSU eventually? Mobo is a Gigabyte EP35-DS4 rev 2.1, yup...one of those Ultra Durable 2's.

I've had this PSU since mid-May '07. The PCB has April 18,2006 stamped, but I don't know if its the manufacturing date or the PCB's revision date. The large filter cap is Nippon Chemi-Con, so thats a good sign, and values are 470uf and 400v. All the other caps have similar color but no branding. When I cracked the case open, I recall a small amount of a maple syrup-like odor. Now I hesitate if its lytic or semicondutor related.

I'm pretty conflicted over what's really wrong with my psu. I'm completely broke so a repair is my only option. Don't worry I've been RTFMing a lot and even more since I got here. Lot's of good info.

[Th3_uN1Qu3]

Re: Corsair HX620

Sounds like bad caps in the PSU most likely. It's not the overclock nor the motherboard i'm quite sure.

I've been running an E6550 CPU at 3.61-3.73GHz for almost 3 years on a P35-DS3. The E6550 has a 7x multiplier and a stock frequency of 2.33, so do the math and see what insane FSB values i run. I have a Seasonic SS-500HT power supply.

[Madcat]

Re: Corsair HX620

My overclock is simply going from 333 to 400mhz. For the life of me I can't figure out why going past 400mhz would prevent POST. Oh well, a 1:1 ratio made me go ^____^

I'm pouring over all the caps on the board. I'm coming to terms that they're Nippon Chemi-Con....possibily KY series? I'll update. Wish I had a camera I'd post my PSU on here.

Edit: I dig your response time, you must not get enough sleep, huh?

[PCBONEZ]

Re: Corsair HX620

I don't see anything that absolutly points to the PSU.

Corsair HX620 is not likely to use unbranded caps.
Chemicon often just uses a logo to brand their caps.

.

[Madcat]

Re: Corsair HX620

Well I've been looking even more this time with a loupe. MKQ series is the input lytic while the output filters are KY series. I find it really annoying when there isn't some tiny logo or lettering to give away the maker.

PCBONEZ: Yeah I'm conflicted about my hardware, so I'm planning to use a PSU my buddy has for his 3-month old I built for him. If theres any powering down, yeah....I'm gonna be super pissed. I didn't go balls-out on the overclock.

[Rulycat]

Re: Corsair HX620

What RAM have you got? Some RAM is picky with some boards about overclocking.

[PCBONEZ]

Re: Corsair HX620

Yes but this was working fine and then quit.
.
Although OC can stress RAM too.
Maybe it croaked, but I would expect beep codes if so.
.

[Rulycat]

Re: Corsair HX620

OP maybe you can run MemTest to check the RAM hasn't gone up the creek?

[Madcat]

Re: Corsair HX620

Well RAM is ruled out since I have three pairs of sticks. I have an OCZ "vista upgrade" 1gb pair, a faulty pair of Corsair DHX 2gb, and a brand new pair of A-Data 2gb.

All of them passed Memtest86+ with no errors after several passes. None of the ram have been through overclocking. Somehow the Corsair DHX pair always crash my system stock or overclock. Their voltage is 2.1v on the label, and even then they cause bsods and crashes. The other two pairs of ram I would run at 1.8 or up to 2.1. They were pefectly fine at 1.8v.

My overclock is going from 333 to 400mhz front side bus. Voltage is 1.3625v to rule out instability from voltages. The northbridge and fsb voltages are up by two ticks in the bios. I don't exactly recall but either was .1 and .05 volts higher than "Normal". Those two voltages stabilized the OC to "rock-solid".

Regarding beep codes, I never EVER get any. Even after cutting 120V from the psu for a few mins, then putting the system back on, it will POST fine overclock or not.

[Madcat]

Re: Corsair HX620

OK folks, I'm browsing now for some exact replacments to all the Chemicons on my Corsair HX620. I'm tempted to replace the large input filter cap too. This psu was running every day for about 3.5 years, so it wouldn't hurt to change all of them. I understand completely where you are coming from PCBONEZ, I've always kept the mobo and cpu on my mind besides the psu. It will cost a few bucks but at least I get the "lytic" variable out of the equation, eh? I wish I had some extra cash for an ESR meter and hot air rework station. I'd test every cap on the motherboard over and over.

From what I've been reading from Chemicon pdfs, The KY, KZE, and KZH series of caps on my psu are "high frequency use". The large input cap is general purpose KMQ. I cannot find a 25V-68uf at all on Digi-Key so I'm looking for something with similar ripple and impedance.

Original:http://www.chemi-con.co.jp/cgi-bin/C...250ELL680ME11D
Digi-Key 1:http://search.digikey.com/scripts/Dk...me=565-1834-ND
Digi-Key 2:http://search.digikey.com/scripts/Dk...me=565-2026-ND

[PCBONEZ]

Re: Corsair HX620

You can use a 68uF in 35v or 50v if the can fits the available space.
-
Using higher voltage cap doesn't affect anything in circuit operation.
The rated voltage is just a limit on the cap. - You don't have to achieve it.
-
Going up in voltage is no [direct] advantage other than more options in replacement caps.
.

[indirect] Sometimes manufacturers use higher voltage cap than needed because the can size is bigger.
It is the larger can they are going for because larger cans usually have lower ESR and higher Ripple ratings.
.

[Slakky]

Re: Corsair HX620

These things are warrantied for 7 years, and they usually pay return shipping. If you haven't opened it up already anyway.

[PCBONEZ]

Re: Corsair HX620

That one is 5 years.

[Madcat]

Re: Corsair HX620

Thanks bones, I'll be grabbing a pair of the LXZ 50v-68uf. As for warranty, I broke it as soon as I got it because I absolutely despise fan grills. My cpu cooler and psu don't have grills. To me, they take away some air flow.

[PCBONEZ]

Re: Corsair HX620

You are checking the Ripple/ESR ratings from old to new when you choose replacements?
- Yes?
.

[Madcat]

Re: Corsair HX620

I definitely compared ratings but unfortunately all 3 links I posted don't show ESR, but do show impedance and ripple. I'm not sure if there's a formula to find ESR or it can only be measured. I'm really hoping low impedance for these caps is good along with ESR.

[PCBONEZ]

Re: Corsair HX620

Click on where it says datasheet in the link and it will open right up.
- here -
ESR is under "Impedance" at 20C.

Can also go to straight manufacturers site.

Chemicon [other than KZG and KZJ] don't normally fail.
Lacking some being bloated I wouldn't suspect those are the problem unless something else points to the PSU. [Like system works with another PSU but not this one.]
.

[Madcat]

Re: Corsair HX620

Wow I'm a real genius, I forgot to check the series datasheets themselves. Coffee, coffee, coffee, coffee........

Alright cool, I'm glad I was using impedance at 20C to pick the caps. Little by little my mind's getting back to electronics.

[Madcat]

Re: Corsair HX620

So I got off my ass and finally ordered all the caps I need off of Digi-Key. Now I just sit here fidgeting until I get my caps. I chose caps with the next highest voltage rating, but some I had to go two voltage ratings up to get the same capacitance.