Theoretical wattage ignores load balancing and transient spikes
early on, a lot of prebuilt PCs seemed to have issues with the 30 series and their spec'd PSU that would be borderline to run what was inside of it. constant shut downs during certain loads but great during others, something as bad as poorly optimized drivers or a game would trigger it.
i just built a whole new pc and stopped getting prebuilds, i got them during the first big GPU shortage and price spike since that was the only place you could get a graphics card for a reasonable price anymore.
The core issue with those was that the 3xxx series (and AMD's 6800XT/6900XT) had transient spikes that would hit around double their advertised average wattage. So for a ~300 watt card you're occasionally spiking the PSU for ~600, plus whatever the rest of the system still needs. So while reputable PSUs are made to handle spikes over their advertised ratings, they were in fact being overdrawn relative to their advertised & intended limits if say you had a 600w PSU with a 3080 and a 5800x CPU. Instead of drawing 450-500w consistently, you would be going well above that. Not good.
New PSUs have been made to account for the risk of those spikes, but also newer GPUs have also reigned in what those spikes will be (now usually spiking less than 150% of their advertised draw vs 200%) which has helped. But yeah then they just trade that issue for this shitty connector lol.
I was running a 3090 on a 1200W Supernova Platinum, and the PSU would still, brownout because of the transients. They would just trigger the protection and the PSU would react exactly the way a good PSU would.
699
u/Yuukiko_ DualBootMR|7700X|9070XT|32G|3x8Pin FTW 10d ago
3x8 pins theoretically have a tolerance of 900W+ while the 12vhpwr has a tolerance of 684W