Downgrade = Upgrade

[Forleb]

My system initially used an Enermax Revolution D.F. 850W power supply. It was one of the first parts I got when I was deal hunting to put it together, so I went for a unit beefy enough to handle any GPU I happened to get my hands on. 4 months later... I'm sitting with a 6600 that struggles to break 100W. Paired with a 5600X, this means that my entire system under full load draws like 250W, which is actually so low that it hurts the efficiency of my 850W power supply. Therefore, by replacing it with a Seasonic Core GX-500, my system now sits in a reasonable place on the efficiency curve.

 

Sometimes a downgrade is actually the right move in PC building, and while this is one of very few instances, I just thought I'd share in case anyone less knowledgeable was in the same situation or were planning on getting an insanely overkill PSU. Yes, future-proofing is a valid excuse, but power supplies can be found on heavy discounts regularly these days - I picked my new one up for $40 with patience, so unless you wake up one day and just have to buy everything for an upgrade at once, I'd recommend buying a PSU that's appropriate for the current hardware & worrying about it later. With the way CPUs and GPUs are spiking in price, dropping an extra $100 at most on a future upgrade isn't going to seem bad at all, I can guarantee that much.

[asheenlevrai]

Thanks for the heads up!

 

Is there any noticeable symptoms of using an overkill PSU?

How did you notice the efficiency of the 850W PSU was bad? Was it just by calculating the power consumption of the components?

What's the drawback of being less efficient? Just use more power or would it hurt components/performance?

[seon123]

6 hours ago, Forleb said:

Therefore, by replacing it with a Seasonic Core GX-500, my system now sits in a reasonable place on the efficiency curve.

No, it does not. mUh EfFiCiEnCy CuRvE is just a myth, and is not real, or at least not a relevant factor. The "curve" resembles more of a flat line when you actually graph with the y-axis starting at 0. The graphs you find online are there to show and exaggerate the difference in efficiency, which is why they don't start at 0.

 

From Cybenetics' testing, the Revolution DF 850W is about 90.8% efficient at a 255W load. By changing it to the Core GX-500, which allegedly sits in a more reasonable place on the efficiency "curve", the efficiency is now about... 89.5% at 250W load. Not that any of this matters, as the efficiency should be one of the last things to consider when choosing a PSU. Much like how you'd look at the performance, price, noise etc of a GPU before considering the TDP.

https://www.cybenetics.com/index.php?option=database&params=1,0,33

https://www.cybenetics.com/index.php?option=database&params=1,0,12

Edited December 19, 2021 by seon123
Something something

[Guest]

4 hours ago, Forleb said:

My system initially used an Enermax Revolution D.F. 850W power supply. It was one of the first parts I got when I was deal hunting to put it together, so I went for a unit beefy enough to handle any GPU I happened to get my hands on. 4 months later... I'm sitting with a 6600 that struggles to break 100W. Paired with a 5600X, this means that my entire system under full load draws like 250W, which is actually so low that it hurts the efficiency of my 850W power supply. Therefore, by replacing it with a Seasonic Core GX-500, my system now sits in a reasonable place on the efficiency curve.

What are you.....  Did you plug your PC into a Kill-A-Watt and found it used less power with the Seasonic vs. the Enermax or something?

 

I'd like to know where your train of thought comes from.

[Forleb]

12 hours ago, asheenlevrai said:

Thanks for the heads up!

 

Is there any noticeable symptoms of using an overkill PSU?

How did you notice the efficiency of the 850W PSU was bad? Was it just by calculating the power consumption of the components?

What's the drawback of being less efficient? Just use more power or would it hurt components/performance?

1. None performance-wise

2. 80 Plus clearly states x efficiency at y% utilization, and I just never payed attention to it until now

3. You end up drawing more power from the wall. PSUs have to convert energy to a format that can be understood by the components, and in that process they keep drawing power until they're able to convert enough at any given time. No PSU is perfect at this, thus giving way to the 80 Plus system. It's technically the safest route to go overkill if you have an aggressive OC on 1 component, but the PSU actually has to work a bit harder to regulate percentages as low as mine were.

 

I was very picky with this upgrade, as shifting from 30% utilization to 50% should only bump the efficiency by like 3%. I'll probably end up selling the other unit for a net profit though, which is the other part to consider of the "downgrade = upgrade" argument.

12 hours ago, seon123 said:

Not that any of this matters, as the efficiency should be one of the last things to consider when choosing a PSU. Much like how you'd look at the performance, price, noise etc of a GPU before considering the TDP.

I do agree that general quality of the unit & feature set shouldn't be overlooked, but I'd like you to name 1 person that feels comfortable putting an 80+ Bronze unit in their RTX 3080 system. Regardless of the physical integrity of the unit, its efficiency is a general indicator of the quality of the capacitors, chokes, etc. underneath. Noise and value are the spots I'd look over last since I want my PC to have optimal power delivery - On that note, unless the Enermax unit Cybenetics tested decided to magically become 80+ Platinum, that doesn't line up too well with the 80+ Gold curve. If the term was a myth, why would nearly every PSU on the planet brandish a badge that supports it? Just curious.

[--SID--]

Quality wise the downgrade is enormous and the 12v OCP trippoint of the SS is a bit higher than each 12v rail of the Enermax. That makes it less safer to use.

[Spotty]

49 minutes ago, Forleb said:

I was very picky with this upgrade, as shifting from 30% utilization to 50% should only bump the efficiency by like 3%

The enermax revolution DF is actually most efficient at around 35%. Not that it really matters as it's a gradual decrease in efficiency as load increases. 

80+ only tests at 10% (for titanium PSUs) 20%, 50%, and 100% loads. The minimum requirements for 80+ gold are higher at 50% load than 20% and 100% but that does not mean power supplies are most efficient at 50% load. 

 

Check the Cybenetics test report, much more detailed testing than 80+. Here's what the efficiency curve looks like for the D.F. 850W

https://www.cybenetics.com/index.php?option=database&params=1,0,33

 

Cybenetics is a great resource if you're interested in power supply efficiency. They also have the seasonic core GX 500w and at 250W load it's 89.5% efficient. The enermax revolution DF 850w at 250w load is 90.85% efficient. (For 115v mains)

 

You not only downgraded to a worse power supply but also a less efficient one, all based on a wrong assumption that "power supplies are most efficient at 50% load". 

[Forleb]

Ok, I'll admit that I was wrong here. Moving forward, I struggle to believe the quality downgrade is "enormous" enough to be concerning, as I have a reliable surge protector & have no intent of upgrade the core components of my system. Am I fine just leaving the GX-500 in there, or is there a legitimate general issue that warrants me swapping back to the D.F.? I know I preached about quality control, but truth be told I'd rather sell the D.F. and live with the GX-500 if it isn't a ticking time bomb.

[Dogzilla07]

4 hours ago, Forleb said:

but I'd like you to name 1 person that feels comfortable putting an 80+ Bronze unit in their RTX 3080 system. Regardless of the physical integrity of the unit, its efficiency is a general indicator of the quality of the capacitors, chokes, etc. underneath.

The efficiency of a power supply is in no way shape or farm a reliable indicator of the quality of the internal components, it is at most a rough guideline.

4 hours ago, Forleb said:

On that note, unless the Enermax unit Cybenetics tested decided to magically become 80+ Platinum, that doesn't line up too well with the 80+ Gold curve. If the term was a myth, why would nearly every PSU on the planet brandish a badge that supports it? Just curious.

You'd be surprised how often this happens, the number of power supplies that are shown to be more efficient when properly tested is very large. (If they are similar or more efficient in the most relevant ranges than what their 80+ badges point out, what does it matter what kind of badge they have, or that they achieve 99.5% of what's needed to qualify for a badge ?, when the only tangible difference would be a few dollars more spent on electricity over a period of multiple years)

 

Another cool tidbit of history, the person who wrote the original post on overclock forum, from which the whole wrong assumption that "power supplies are most efficient at 50% load" stemmed from, wrote again later in the same forum topic, that people were misinterpreting and misrepresenting his data, his information, and the point he wrote of all it in the first place.

 

Enough people glazed over that and spread the misinformation and the myth continued to spin out of control for years, and years to come.