[SOLVED] How much power does a PC draw during POST?

[Coleh_Broleh]

Hi there, hope this isn't a dumb question. I have a 3090 Waterforce AIO from gigabyte on it's normal BIOS. I am considering flashing the Kingpin 1000W BIOS so I can use it at 45% 24/7 for gaming at 450W max available power draw. Here's the thing: I don't wanna risk blowing up my AX760W Platinum. If I can't do the BIOS mod without the risk of, at POST/bootup the card drawing on as much power as it may feasibly be able to (seen some people manage to draw 600W continuous from the 3090 with kingpin BIOS) and consequently frying my PSU then it's obviously not worth the risk, but if POST power draw is only 2D power load, I'm thinking I will go ahead with the flash and take the risks. Anyone know for certain if POSTING draws full tilt power, and where I may be able to read indepth about the process for future reference? Thank you!

If it's of any importance, the full build is a 5800X/3090 Waterforce/32GB 3600CL16/2SATA SSDs, 2 NVMEs and 1 HDD all powered by the older AX760W Platinum from Corsair.

 

[Darkbreeze]

Your system will not pull ANYWHERE near that amount during POST. Ever.

Not that I think flashing a firmware version not specifically meant for your card is a good idea, but that isn't what you asked. So as to the power, unless there is a problem with your power supply you have plenty of overhead. After POST however, when the graphics drivers load, at that point it may be a different story.

Personally, I do NOT believe it is worth the risk or the effort, but for a different reason than what it might pull during POST.

Honestly, I'd recommend that if you value that graphics card and other hardware, considering how expensive they are compared to the cost of replacing just the power supply, you ought to seriously consider a new PSU because that one is likely pretty old. Again, in that regard, it's not worth the risk.

 

[Ralston18]

I do not remember ever seeing any issues related to PSU power draw during POST.

What specific problem are you trying to resolve?

If not some problem what are the expected results of doing the flash and gaming thereafter?

For the most part I would not expect to see much improvement per se. Likely not worth the risk.

More information needed.

 

[Coleh_Broleh]

Thank you two for the responses. I was just trying to understand IF the componentry in a PC during POST go to their maximum tilt profile/configurations to check they are functional/work. I was doing this to hopefully know whether or not the GPU would end up pulling god knows what power draw during bootup. I gave flashing the Kingpin profile a shot. It works. With a bit of an asterisk in the form of the attached image. Yeah. 712W peak power draw on a 760W Platinum PSU. It was probably just a transient power spike, but knowing that at any point I could accidentally pull an ungodly amount of power through my PSU when resetting my MSI Afterburner profile is more than enough for me to say "nah. not worth it". It's a real, real shame because the power profiles on the AIO Gigabyte cards are abysmal. The F1 non rebar BIOS is locked to 390W which is reasonable given it's a 2x8 card(though that an AIO card is 2x8 is a whole other bag of "what the hell gigabyte", whereas their ReBAR bios artificially limits you to 350-360W. My brand new card cannot even sustain it's factory boost clocks under the rebar BIOS, a well documented issue on other forums. I wanted to see if I could rectify this and get a 450W power budget for the card, but seeing how this plays out with the Kingpin BIOS I'd rather not ever risk some crazy <Mod Edit> like this. It's a real, real shame because this card frankly doesn't clock. At all with stock BIOS, but I guess i'm just stuck like this. Really frustrating for a £2000 card but, what can you do? Better to have a card than not in current climate. Thank you again for the responses!

 

[Darkbreeze]

No, the system will not pull anything near maximum power during the POST process.

Now, where some might get confused about this is the fact that IN THE BIOS the CPU will generally use significantly more power than it does while in Windows, at idle or low load states, because while in the BIOS (Traditionally anyhow) the CPU won't go to a low powered state and will have all cores active, so you will generally see higher CPU core temps while in the BIOS than you will in Windows or another OS with a single core or even a couple of cores lightly loaded or at "idle", whatever "idle" is supposed to mean. CPUs are rarely ever actually at idle, but after several minutes have passed since booting to the desktop and all your required processes have loaded into memory, it will generally see a major reduction in usage, power consumption and core temperatures, as it "rests" in a semi-idle state.

In the BIOS that generally won't happen. During POST it will usually not use as much power from the CPU as it does while in the BIOS, unless you've specifically enabled the configuration setting to allow multithreaded performance DURING the POST process. Usually, it does not without that setting being enabled, but even so, that is a small fraction of overall power consumption when we're talking about a flagship card like the 3090. THAT is where the majority of your power consumption will normally come from, so long as you have a pretty decent tiered card AND so long as there is no fat overclock configured on the CPU. Even so, in either of those scenarios, power consumption is generally fairly low during POST until Windows takes over and begins loading full featured drivers.

At that point, power consumption will go up, but will also generally go back down once you reach the desktop.