PSU

Glenn Haggerty

Posts: 141   +48
TechSpot Elite
I recently Upgraded my GPU from a 3070 to a 3080 and I already had a 750w PSU which is the recommended minimum by Nvidia. My PC would start crashing once or twice a day or my monitor would shut down once or twice a day and say it was not receiving a signal. So I replaced the EVGA gold 750w with a EVGA Gold 850w and after a week I have not had any problems. So judging from my own experience I would say that a 850w PSU is the minimum and I wish I had bought the 1000w for more head room or future upgrades. I always thought for the most part that if you PSU did not have the power, your PC woudn't boot.
 

cliffordcooley

Posts: 12,993   +6,311
I'm not completely certain. I don't think the system is pulling a full load while booting. Your voltage levels will differ under different load levels.

Interesting! I wonder if this will happen to everyone. Or if you drew a bad straw in system parts and configuration.
 

Glenn Haggerty

Posts: 141   +48
TechSpot Elite
I have a ryzen 5600x which is kind of a middle of the road cpu that shouldn't draw too much, I did upgrade my ram which went up in voltage from 1.35 to 1.40, I don,t think that would put it over the mark unless it was at the brink already. Anyway it's always good when you have a PC glitch (it drives me crazy) to solve the problem
 

captaincranky

Posts: 17,379   +6,130
I always thought for the most part that if you PSU did not have the power, your PC woudn't boot.
That's not even close to being true. I doubt it requires much more than idle power to POST and boot a PC. An outright defective PSU will cause failure to boot, but most likely not one that is too weak for full stress.

For reference, I have an i5-6600k (stock speed), and a GTX-1050 ti 4 GB "FTW" edition. (dual fan). The PSU is 500 watts.

Since I don't game, and the fans in the card are set to trigger at 50 C, I've never ever heard or seen them start. That's doing easy stuff like running Photoshop or playing DVDs. (We are up-scaling to 2K though)

A PC won't black screen until a voltage drop occurs on any given rail to below tolerance. Usually it's the 12 volt rail, and an overclocked CPU and/or humongous video card that are the culprits.

There is software around to stress test your PC. Although I'm way out of touch with what's currently available. I think it used to be "Prime 95", not sure now though
 
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Glenn Haggerty

Posts: 141   +48
TechSpot Elite
That's not even close to being true. I doubt it requires much more than idle power to POST and boot a PC. An outright defective PSU will cause failure to boot, but most likely not one that is too weak for full stress.

For reference, I have an i5-6600k (stock speed), and a GTX-1050 ti 4 GB "FTW" edition. (dual fan). The PSU is 500 watts.

Since I don't game, and the fans in the card are set to trigger at 50 C, I've never ever heard or seen them start. That's doing easy stuff like running Photoshop or playing DVDs. (We are up-scaling to 2K though)

A PC won't black screen until a voltage drop occurs on any given rail to below tolerance. Usually it's the 12 volt rail, and an overclocked CPU and/or humongous video card that are the culprits.

There is software around to stress test your PC. Although I'm way out of touch with what's currently available. I think it used to be "Prime 95", not sure now though
Well captain, I 'm learning something new all the time, you could fill many libraries with what I don't know. But I did find the real problem was my GPU wasn't seated right and once I reseated it I have not had any problems. I did upgrade my PSU from a 750w to a evga gold 850w (thank God I didn't buy the gigabyte). Nvidia recommends a 750w minimum for a 3080, so just for the head room, peace of mind and future upgrades I went with the 850w.
 

captaincranky

Posts: 17,379   +6,130
Well captain, I 'm learning something new all the time, you could fill many libraries with what I don't know.
As I understand it, that's why we have libraries in the first place.
But I did find the real problem was my GPU wasn't seated right and once I reseated it I have not had any problems.
Consider yourself very lucky you didn't damage the card.
I did upgrade my PSU from a 750w to a evga gold 850w (thank God I didn't buy the gigabyte). Nvidia recommends a 750w minimum for a 3080, so just for the head room, peace of mind and future upgrades I went with the 850w.
As with many things, having a bit too much is far better than having too little. Within reason, of course. IIRC, the max system draw should only be about 80% of the PSU's capacity anyway.

Most of the PSU suppliers have calculation tools to assist you in making a choice of wattage. A few minutes of searching revealed they haven't been kept up to date.

But Newegg, (of all people), listed the components in your system. Being somewhat self serving, I calculated the needs of my main system instead. So, I came up with 352 watts, with 500 watts installed. (I guessed right on my own. Do we have a "patting oneself on the back emoji")? :rolleyes:

Anyhoo, here's the link in case you'd like to toy around with it on your own:

Keep in mind I doubt very much that algorithm takes into account any overclocking you might perform on the CPU.
 

Glenn Haggerty

Posts: 141   +48
TechSpot Elite
As I understand it, that's why we have libraries in the first place.

Consider yourself very lucky you didn't damage the card.

As with many things, having a bit too much is far better than having too little. Within reason, of course. IIRC, the max system draw should only be about 80% of the PSU's capacity anyway.

Most of the PSU suppliers have calculation tools to assist you in making a choice of wattage. A few minutes of searching revealed they haven't been kept up to date.

But Newegg, (of all people), listed the components in your system. Being somewhat self serving, I calculated the needs of my main system instead. So, I came up with 352 watts, with 500 watts installed. (I guessed right on my own. Do we have a "patting oneself on the back emoji")? :rolleyes:

Anyhoo, here's the link in case you'd like to toy around with it on your own:

Keep in mind I doubt very much that algorithm takes into account any overclocking you might perform on the CPU.
I checked that newegg link which was calculated at around 600w ,so I probably wasted my money, which wouldn't be the first time. The info I had read which inspired to buy a 850w is below and this and other sites pretty much say the same thing.
RTX 3080 requires 750W PSU. To have RTX 2060 in the same system requires additional 160W. So 900W-1000W PSU.Jan 25, 2021

[HEADING=2]Question - 750w enough for 2 GPUs? | Tom's Hardware Forum[/HEADING]
https://forums.tomshardware.com › threads
 

captaincranky

Posts: 17,379   +6,130
I checked that newegg link which was calculated at around 600w ,so I probably wasted my money, which wouldn't be the first time. The info I had read which inspired to buy a 850w is below and this and other sites pretty much say the same thing.
RTX 3080 requires 750W PSU.
Graphics card manufacturers typically pad the power requirements quite a bit. It's a liability thing. The 2060 requiring so much more juice than the 3080 is a puzzlement though.

Don't fret. I waste money all the time, buying tools I may never need, guitars I never play, and on.

Keep in mind, "he who dies with the most toys wins", and now you've got a hefty spare to boot.