Could GPU overclock have blown PSU?

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Ok here's the deal. I recently put an old HD7950 into my son's PC. Because it's a weak card relative to the CPU (Ryzen 1600) I decided to overclock it and bumped up the core yesterday from 800 to 950. I haven't previously overclocked this GPU in this system. My son played a bit yesterday and apparently left the game running when he finished.

I went to turn on the machine today and to my surprise it was completely dead. No beeps, no lights, no fans, no nothing. I tried removing all the devices including GPU to reduce power consumption, still dead. Interestingly after I tried another power lead, when I flipped the psu switch back on, it let out a brief flash/spark at the back of the PSU. To be fair I've seen this once or twice in the past from other PSUs without any issues arising.

I know that the 7950 is a power-hungry card (1x8pin 1x6pin) so when overclocked I assume it draws even more power, even though I didn't touch the voltage yet. The PSU is a OCZ Powerstream 470W, about 15 years old although it's only had light usage for the past 10 years or so (not in my main rig). It doesn't have any PCI-E connectors so I have it rigged up with with molex adapters and also only has 2x SATA power so again I have 1 adapter for the 3rd SATA drive. Basically it's a bit Heath Robinson, but never had any issues when it was running an RX480 (single 6pin power).

I tried the PSU in another machine that works fine with a weaker PSU, completely dead. So I'm fairly sure the PSU is knackered. What I don't yet know is whether any other components are damaged, as I don't really want to tear down my main PC to put the PSU from that in it. So I've got a replacement PSU coming tomorrow, the OCZ whilst a pretty decent unit for its time was probably due replacement anyway for something a bit more modern.

The one piece of the puzzle I'm unsure about is whether the GPU overclock was the cause or just a co-incidence. Has anyone seen something similar?
 
Man of Honour
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New Psu installed and it works, seemingly no damage to other components thankfully.

Was a bit worrying though, when I first hit the switch nothing happened, figured it may have blown the fuse in the plug so swapped the kettle lead for the new one and it was OK.
 
Man of Honour
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Technically I'm not sure the PSU was officially underpowered or particularly cheap, an online calculator suggests I need a 345W PSU to run that system (maybe a bit optimistic, let's say 400W as the GPU alone has 200W TDP) and it had an RRP of $130 back in 2004 which is the equivalent of $185 today. The 12v rail is also rated the same as a the 520W model. Also has these dials on the back that let you adjust the 12v/5v/3.3v rails to keep them in tolerance under load. Heavy unit, frequently recommended on these forums, I really don't think it was that bad back in its day.... but its day has passed, and it is perhaps unreasonable to expect a unit of that age to cope with more modern components :) Part of me wonders if the real issue was the lack of dedicated PCI-E power, routing through adapters always feels a bit of a compromise and maybe that's what pushed it over the edge.

For my main rig I am a bit more fussy (after a bad experience with a NorthQ 850W unit that literally went pop with a loud bang in 2009 - ironically I only got that PSU because I was concerned about the 470W PSU running my upgraded system!), but in secondary systems I'll put in budget PSUs within reason.
 
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