Graham Sutherland / Polynomial

3 days ago

wiggling the connector around does nothing though. I see no fluctuation on the multimeter at all and, no matter how I apply pressure to either end, the old PSU (which works fine, so sadly I bought a new PSU for £120 for no reason) will not power on with this cable. extremely bizarre.

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3 days ago

the only thing I can think of is if the cable somehow thermal cycled in a weird way and the contacts are *only just* making contact so when plugged in it's showing 230V when unloaded but the contact resistance is high enough to tank the mains voltage as soon as it tries to power on? but then you'd think the PSU would hiccup rather than just not powering on (I guess maybe mains UVLO protection could prevent that or something? idk)

this is one of the weirdest failure cases I've ever had

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3 days ago

@davidmc disks came up fine, scrub in progress.

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3 days ago

@0x47df I'd think that physically moving the connector around would make it connect in that case though. it's really really weird.

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3 days ago

I've tested continuity and resistance. the cable is fine. L-L, N-N, G-G, no continuity between the lines, resistance reads good (within 10% of other IECs I have). it's been powering my NAS for *years* without issue. I get 230V on the output when I plug it in. but *neither* my old PSU or new PSU will power on when plugged into it.

I am *SO* confused

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3 days ago

this is a straight IEC-IEC, no fuse, it's just regular copper wire. and I read 230VAC just fine over it. but the PSU won't power up with that cable.

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3 days ago

I was fumbling around a bit trying to plug stuff in 'cos it's pretty cramped back there, and when I look in with my phone light I notice that the new cable is actually plugged into the *exact same port* the old cable was. the port is fine.

plug the old cable back in and try it. doesn't work. plug the new cable in. it works.

what the actual fuck

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3 days ago

so I go downstairs with it and I'm about to file an RMA, and I think "hmm, maybe it just doesn't like the UPS? better check before I RMA it".

so I plug it into an IEC cable downstairs, bridge PS_ON, and bam! works.

so is it the UPS????

I go back upstairs, try again, yup still dead. and I'm still seeing 230V.

I grab a new IEC-IEC lead to test another port on the UPS, and it works! so what, one of the UPS ports is somehow presenting 230V but... not good enough 230V to work? wtf

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3 days ago

first: gotta verify that the new PSU works. I measure +5VSB on the ATX24 and get 0V. so I bridge PS_ON and GND, and check the other rails. nothing. I see the briefest flicker of a few mV, maybe, but it doesn't power up. I'm starting to think the new PSU is DOA and I just got super unlucky.

I verify mains again. 230V on the dot. just to be sure, I go check that my multimeter is reading DC correctly. yup, it's fine.

at this point I'm really thinking I just got a dead PSU, or the board killed it.

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3 days ago

my NAS died a couple of days ago with zero sign of life. no lights at all on the board, not even standby LEDs. it's going to my UPS, so I checked that I was seeing 230V at the cable, and I did. so I figured the PSU is dead, because the motherboard would need to be ultrafucked for it to show literally no signs of life.

ordered a new PSU. it arrives. swap it in, aaaaand... nothing. ugh. so is the board dead? maybe a hard short over +5VSB or something?

so I start digging further.

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3 days ago

fuck me this NAS repair has been frustrating and cursed

still getting it back online, then I'll do a thread because what the actual fuck

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3 days ago

@erincandescent turns out the manual I have for this PSU is completely wrong. the manual says it has ATX24 plus two 4+4 CPU cables permanently wired. what it actually has is ATX24, one 4+4 CPU cable, and two PCIe 6+2 cables permanently wired. but for some reason it also has two additional modular slots for PCIe 6+2.

some still less cursed than what I just went through though. (post pending)

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3 days ago

I'm so confused though because this PSU is supposed to have non removable CPU power, and these are the non removable connectors

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3 days ago

@erincandescent now I'm *really* confused because these are the non-removable cables on this PSU which are *supposed* to be the CPU ones

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3 days ago

@erincandescent ... wait... did I just spent 15 minutes trying to plug the wrong cable in? T_T

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3 days ago

a pox on whoever invented those horrid little split 6+2 pin CPU power cables that invariably separate every time you try to get them in an 8-pin slot. I've just spent 15 straight minutes trying to get this thing in and all I've got to show for it is back pain and scratches all over my hands.

EDIT: oh for fuck's sake 6+2 is PCIe not CPU I am such an idiot

EDIT 2: ok the manual was actually wrong which is what confused me. it said it only had 2x EPS12V hardwired but it had 2x PCIe and 1x EPS12V

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3 days ago

@timonsku but yeah the Rufus feature where it detects you're flashing a Win11 image and it asks if you want to disable the TPM check is super convenient.

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3 days ago

@timonsku you don't even need the "remove TPM check" trick on the media, it's just a convenience; when you hit the standard install step where it complains about no TPM there's a button at the bottom somewhere that you can click to get to the "continue anyway" option.

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3 days ago

@timonsku you can also just say "ok I don't care" during the installation and it'll warn you that your hardware is not supported (i.e. you will not be able to get support from Microsoft for things being broken, but... like... when do you ever get useful support from Microsoft as a home end-user?) but still install just fine.

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3 days ago

electron bean lithography

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