EVGA SuperNOVA 750 G+ 80 Plus Gold 750 Watt Fully Modular Power Supply Expired

this, or the newegg Seasonic Focus 750? which is better for RTX3000 series card?

Wondering the same thing myself. This is $20 cheaper with no rebate or Newegg. Seasonic is platinum rated, so a few % more efficient, and is LTT "Tier A" vs this is "Tier B". Not sure if that's worth $20 and rebate hassle.

Both have an ECO mode and 10 year warranty.

750W is plenty for RTX 3080 or below.

According to the PSU tier list: https://forums.tomshardware.com/t...s.3624094/

G5 is a high quality mid range system builder PSU.

On par with the Seasonic units but not quite at the level of corsair units. A solid option at this price and the fact that its available.

this, or the newegg Seasonic Focus 750? which is better for RTX3000 series card?

For those concerned "is this enough for XYZ", just add up peak watts of the devices: CPU (65/90/105/125), graphics (3080 is 350w, 15w/stick ram, 10w for AIO 240mm water cooling, 3w/fan, 3w/SSD, 7w/M2 nvme.

Typically, most PSU are most efficient ~50% load (not use the least power)!, however, each psu has diff efficiency curves. the higher 80+ Rating, the more efficient relative to same wattage PSU.

https://www.tomshardware.com/revi...,4193.html

I have a whole rant about PSU efficiency I've been meaning to share. To some people it won't be news, but I think most people are like me.

I have been using over-rated psus forever because a) I thought it would be easier on the electronics so they would last longer, and b) I looked at the efficiency curves they publish and as you say it's higher in the mid range. So getting one rated twice as much as the components need is good right?

Well, no.

Most of the time I'm not gaming while mining for bitcoin (most..) so some components are simply not drawing their peak power. It almost never happens for a normal user or gamers (most users). When gaming you're probably pushing your graphics card to 3/4, at most, consistently. Even on an insane rig. Your cpu is doing very little during games now, they offload everything to the graphics card. So the amount you need might be lower than you think, unless you're doing literally focused data processing like mining bitcoin.

And now the key point - they never show it but at the very bottom of the efficiency curve, around 10-15% utilization, the efficiency of PSUs plummets. It's lower there than anywhere else.

I've adjusted my PSU buying such that I try to get the LOWEST watt rated PSU I can for my setup. My computer spends 95% of its life at basically idle, drawing between 65 and 100w. So having a higher efficiency at this range beats having it at the high end.

It's a little complicated to say absolutely but 99.9% of people are better off shooting for low end efficiency (get the maximum rating as close as possible to peak power use).

And making that decision isn't simply comparing hours idling vs gaming, but it is close. The exceptions are at extreme power use and extreme PSU price. The really high end (platinum rated) PSUs have better low end efficiency as well as high end, so in some cases you can get the best of both.

But normally the math works out like this:
If I'm getting 80% efficiency at 100w (a bit high for idle but makes the math easy) I'm wasting 20w. If the efficiency drops to 40% at 100w then I'm wasting 60w. So by PSU choice I might be wasting 40w. That's the kind of differences that happen on the low end comparing a well rated PSU vs an overrated PSU.

Compare that to If I'm gaming and I'm using 500w and my PSU is 90% efficient, I'm wasting 50w. If the efficiency drops to 80% (really about the worst drop you'll find between a high end to low end CPU) I'm wasting 100w. So comparatively I'm losing 50w to the wrong PSU.

As you can see, we're losing almost the same amount of power at the low end (40w) as the high end (50w) because the efficiency drops at the low end are so severe. But in this case if you spend more time at 500w draw than at 100w, then the higher rated PSU would be better.

And as to my other theory that it's easier on the PSU components to be overrated. I'm not an EE but I believe that isn't true. Wasted power is lost as heat, which is what hurts the components. So you still just want to maximize efficiency. I would even say the low end heat loss is worse because the fans are generally set to low for noise, but as we saw above the amount of heat being dumped into the components is about the same. So the heat does more damage.

Of course you have to consider your specific case, but this has changed how I buy PSUs. I used to overshoot what I needed by about 1/2 (500w goes to 750w) and figured it had the bonus of leaving room for future expansion. It's also one of those consumer tricks - I felt like spending more must mean I'm getting more. I think the PSU companies market that way too, pushing the belief that more power is just better. Now I try to get a high quality PSU (higher efficiency ratings) and focus on low end efficiency (minimizing the power overhead). So instead of getting a 750w gold PSU, I would get a 500w platinum PSU (assuming peak power is 500w).

One note in my defense for using overrated PSUs for a long time...
I do think that back in the day having a higher top end on the PSU was helpful when you had a lot of accessories.. HDs, CD drive, Burner drive, flash drives, etc. Just in my experience, but I think this was because of how power was distributed. My guess is there a design flaw due to not predicting the success of USB. The USB power is supplied from the 5V rails, as are a lot of things. I think the power to that rail seemed to be achieved through splitting off the PSU, which meant the max power to USB devices would be a fraction of the maximum PSU wattage. I'd find that plugging in too many (not self-powered) USB devices would cause the whole USB rail to fail (voltage drops too low, the motherboard responds as if the entire USB hardware system was unplugged and then plugged back in). It wasn't like my USB devices were drawing anywhere near the max power of the PSU (average USB drawing only 5w), so I found it confusing that my lower rated PSUs would have this problem but my higher (850+) wouldn't. But if the rail could only handle a fraction of the total PSU power, and they were hitting that, then a higher rating fixed that. This sucked because it would randomly disconnect USB devices, or windows wouldn't recognize the USB hub at all until a reboot. So I tended to keep buying high power PSUs even for non gaming.

But I haven't had that problem in a while.. I think they've gotten better at properly supporting the 5V rail these days.

Anyway, hopefully that rant helps relieve someone of the "more is better" mindset. 750w is super overkill for practically everyone, including gamers.