Which PSU should I buy?

Alexander Martinez said:Look, you're famous for suggesting someone grab a thousand-watt power supply for a build like this, but there are actually people out there who own things called power meters. They have similar setups right in front of them, so a manual reading probably carries a bit more weight than your sarcasm.😉

It’s a 100W rig, like I said, and honestly, I don't really care what your take on it is.😁

Everyone is entitled to an opinion, even if it happens to be wrong, I suppose. It would just be a shame if something happened to someone and I felt responsible because I told them everything was fine when it wasn't—like, maybe they could have gone for something slightly higher quality to avoid a total system failure.

Then you guys can come after me and say, "Hey, you messed up, you ruined his machine."

Has anyone here actually defended using a 400W unit like it's some holy grail? I mean, has anyone admitted fault when a PC crashed because the power supply was overcompensating by pumping out way more juice than needed just to stay alive?

Nobody has. I once had a 550W unit that was supposed to deliver 400W from a reputable brand, but as soon as I swapped out the CPU, motherboard, RAM, and GPU, the whole thing started freezing constantly. I went out, picked up a Seasonic or one of those generic ones that looked like it was just rebranded 650W junk from Best Buy, and everything worked perfectly right away without any freezing.

And what's the alternative? Just tell everyone not to buy off-brand power supplies and stick to the big names? You might as well laugh at that suggestion.

Here is a little correlation for you regarding Grundig Germany (which doesn't exist anymore) versus Grundig Turkey (which does).

It's like the name Bernd; what do you call Vivax, which is just a generic name? Both are sold in our market. There isn't much difference between a brand name and a generic one, except that with a brand, you're basically paying about 60% of the price just for the logo.

All of this stuff is manufactured in China, Korea, Taiwan, Singapore, and various other Eastern territories used by Western manufacturers.

I’ve been running an identical setup with a 380W power supply, and it’s worked flawlessly for nearly two years now. I can tell you from experience—and I've seen plenty of others do it too—that people regularly push much more demanding rigs on power supplies in that ~400W range without a single hiccup.

This isn't just my opinion; it's a matter of fact.

Alexander Martinez said:I’ve had an identical setup running on a 380W power supply for nearly two years now without a single hiccup. I can think of plenty of people who have pushed much more demanding rigs on power supplies in that ~400W range without running into any issues at all.

That isn't just my opinion; those are just the facts.

You're basically just gambling, and I once ran a rig for two years straight before I decided to upgrade, and then—poof—everything just gave out.

The power supply is really the foundation of everything, much like the motherboard; if you pick something that works fine today, it might not be ready for whatever comes next.

He could probably get away with that 400W unit, but once he starts getting into upgrades and actually tries to beef up his PC, that's when he's going to feel the squeeze.

If he just goes for a 550W or 650W unit, he'll have enough headroom for everything, including future upgrades with higher-end components, without constantly worrying about running out of juice.

A decent 400W power supply—one actually built with quality components—will handle a Core i7 paired with a GTX 460 without breaking a sweat. That’s a pretty serious upgrade considering they're currently stuck with 🙂
.

Morgan Moore37 said:I've been there—I pushed my rig through two solid years of constant use before finally deciding it was time for an upgrade, and then... poof. Everything just gave out.

The power supply is essentially the foundation of everything—just like the motherboard. I suppose if you opt for something that seems adequate today, it might not actually hold up for whatever comes down the line.

He can certainly get away with that CX400W for now—I suppose that’s fine if he's just idling—but once he actually starts diving into serious upgrades and tries to beef up the rig, he's going to run into a wall. He'll see exactly where he messed up then.

If he goes with a 550W or 650W unit, he’ll actually have enough breathing room for everything—including future upgrades to more powerful components—without the constant fear that his power supply might fall short.

Well, it all really depends on what you're planning to pair this with—everything is relative, I suppose. If you’re trying to slap a 5970 onto a CX400W, then obviously, you’re going to run into trouble; there just won't be enough juice. But if you go with something like a 6850, well, who knows? Maybe it'll hold up, maybe it won't. That’s why I always say you have to think about the end goal—you need to decide exactly what you want to do with the build and then find the most logical solution that fits within your specific budget. It’s a balancing act. Modern cards are getting much more efficient, too—the performance-per-watt ratio is significantly better now than it used to be. My current card pulls over 150W when it's actually being pushed, yet these newer models could eat it for breakfast while consuming the same amount, if not less. Which, I guess, suggests my current power supply might actually handle an upgrade to a mid-range card and a new processor—assuming we're strictly talking mid-tier hardware, of course.

Thomas Martin4 said:Well, I guess it all depends on what you’re actually upgrading to... if you try to slap a 5970 on a CX400W, obviously it isn't going to cut it, but if you're looking at a 6850, who knows if it'll even run? That's why people always ask what your plans are for the build—you really want to find the best possible solution for whatever budget you have. All these newer cards seem to have a better performance-per-watt ratio. My current card pulls over 150W when it's actually working hard, and I think the newer stuff would just eat it for breakfast while pulling about the same or maybe even less. So, I suppose my power supply should be able to handle an upgrade to a new GPU and processor, assuming we're talking about mid-range cards, of course.

I wouldn't say you're 100% sure about that.

There was a chart posted here on the forum regarding GPU power consumption, and those graphs actually showed the exact opposite—that newer cards are drawing more power than the old ones.

Logically speaking, your argument would hold water if manufacturers weren't constantly cramming more and more components onto the boards that require more and more juice.

If a card from twenty years ago had the same component layout as one today, then maybe we could say they're getting more efficient, but if you compare a card from ten years ago to one released a few months back, you're looking at a massive amount of new hardware packed onto that little piece of silicon.

I mean, why do many modern cards have two sets of 6-pin power connectors on the end while the older ones only needed one? To me, that suggests these things are definitely pulling more power.

Morgan Moore37 said:Are you absolutely certain about that?

There was a chart posted here on the forum regarding GPU power consumption, and those graphs showed the exact opposite—that modern cards are drawing significantly more power than the older ones.

Logically speaking, your argument would hold water if we weren't constantly adding more and more components to these cards, each requiring more electricity.

If a graphics card from twenty years ago had the same component layout as one manufactured today, then perhaps we could say power draw is decreasing. But when you compare a card from ten years ago to one released a few months ago, you see an increasing number of new features packed onto that piece of silicon.

Why is it that newer cards often feature dual 6-pin connectors for extra power while older ones only needed one? That seems to suggest—to me, at least—that these cards are indeed consuming more.

Well, I am fairly certain that the GTX 460 and the Phenom II will be adequately powered by this VX unit. If a CX400W can handle a 5830 paired with an Athlon X4, then this should be fine too. If I were planning on buying something more high-end, I might consider a new power supply. Under load, my current configuration doesn't pull more than 250W—or maybe 300W if you want to be safe (though those figures assume overclocking, which isn't what I'm doing). I suppose that means new components won't cause issues since they consume roughly what I'm currently using...
"I don't know why" they put 2x6-pin connectors on some cards (some need them, some don't), but it doesn't change the fact that a CX400W can easily run something like a 9800GTX+. I installed a card like that in a friend's build with that exact power supply, and it has been running flawlessly for a year and a half now. Even though the box says a minimum of 550W is required, it doesn't specify the manufacturer. And we all know it isn't the same thing whether it's MS or Seasonic.

Thomas Martin4 said:I mean, I'm pretty sure a GTX 460 and a Phenom II will be perfectly fine with this VX unit. If a CX400W can handle a 5830 paired with an Athlon X4, then this should work too. I guess if I were actually buying high-end gear, then maybe I'd bother looking at a new power supply. Under load, my current setup doesn't pull more than 250W—or maybe 300W if you want to be safe (though those numbers are based on overclocked builds, which isn't really what I'm doing here). So, I suppose that means new components won't cause any issues since they don't draw much more than what I've already got...
"I don't really get why" they put dual 6-pin connectors on some cards while others don't need them, but it doesn't change the fact that a CX400W can easily run something like a 9800GTX. I actually put a card like that in a friend's rig using that exact PSU, and it's been running flawlessly for about a year and a half now. Even though the box for the card might recommend a minimum of 550W, they never specify the manufacturer. It’s not the same thing when you're comparing MSI to Seasonic.

Well, it's true that MSI isn't quite the same as Seasonic, but even within Seasonic, you have different tiers that act like two totally different products. And obviously, price plays a role in all of this.

The reason is simple, really—when it comes to electronic parts like capacitors and resistors, there are various levels of tolerance. Higher-end devices use better quality components, which drives the price up, whereas a device built with cheaper components will naturally cost less.

Then you have voltage regulators that can smooth out the power perfectly, versus regulators that just can't manage it (looking at you, budget manufacturers).

In all of this, the transformer plays the most significant role, and it's usually the most expensive part of the entire power supply.

Morgan Moore37 said:It's true that MS isn't quite on the level of Seasonic—though one might argue Seasonic itself markets two distinct tiers of products. And, well, obviously, price plays a role here.

The reason is rather simple—when dealing with electronic components like capacitors and resistors, you encounter various levels of tolerance. Higher-end devices utilize superior components, which naturally drives up the cost, whereas an identical device built with inferior parts will be cheaper.

Then there are the voltage regulators; some are designed to smooth out voltage perfectly, while others—perhaps due to manufacturer shortcuts—simply cannot manage it.

In all of this, the transformer plays the most critical role, and it is usually the single most expensive component in any power supply unit.

That is precisely why testing exists, along with the collective experience of users who have likely fried their hardware; it allows us to determine which PSU is actually suitable for specific tasks. Nowadays, for a mid-range PC, a Seasonic unit in the 425W to 430W range is more than enough. Most standard builds simply don't draw more than 300W. It’s only when you install a beast of a GPU, or perhaps several in an SLI or CF setup, and start pushing extreme overclocks that you actually need something more substantial. No one on this forum wants to see someone's rig die because of a cheap power supply. The goal is always to find the most reliable option for a given budget. If I disagree with someone's build, I usually suggest they invest in quality rather than just chasing high wattage from a unit that doesn't even hit 70% efficiency. For the average user, buying anything over 600W—which is arguably overkill anyway—is probably just throwing money away.

So, you’re out here suggesting 400W while I’m leaning toward 600 or 650W, but hey, to each their own, I guess.

Besides, you've also got those branded power supplies that come under specific names, so that's probably another factor to consider.

I think Thomas Martin4 makes a better point here. What’s the logic in buying a 1000W power supply if you actually only need about 300W? Why bother with a 650W unit when half of its capacity is just going to sit there unused? Is this specifically for CF/SLI setups? Honestly, if someone has enough extra cash to justify that kind of overkill, they might as well just put that money toward a better graphics card right away.
It isn't really about whose recommendation carries more weight; it's just a fact that the average user won't need more than a high-quality 430W unit, even if they decide to overclock.

Look, if a 400W unit shows up $133 whereas a 600W one arrives $183 you can't really buy anything meaningful with that price gap, but for that extra bit, you’re basically buying peace of mind.

Then you go ahead and tell the guy, "Hey, just grab the 400W; take the money you saved on my power supply and put it toward a better GPU"—and what actually happens? The whole system just freezes because it doesn't have the juice to stay running.

I probably wouldn't advise someone to jump up to a 650W unit unless I was absolutely certain they wouldn't end up needing it anyway.

Okay, so maybe a 400W unit works fine for a top-tier Pentium 4 setup or a single-core rig hitting 3GHz. But for anything else, I guess you should bump it up by another 150W. So, for those single-core builds at 3GHz or higher, or maybe dual-core setups up to around 7GHz, or even triple-core rigs averaging 1.6GHz per core, you're looking at 550W. For everything else, I'd say stick with 650W.

Good grief, I don't think I've encountered this much misinformation in years 😁

It’s pretty clear you're just making things up as you go without any actual experience... please, just step away from the keyboard 😉

So you say I'm talking nonsense? Fine. If my experience with builds like this is that they're unreliable, then whatever you say.

Every single configuration similar to this one I've seen worked perfectly fine—no freezing, no stuttering, nothing.

I’ve been messing around with computers for over 20 years now. I actually started with my very first machine that ran real Windows; it was an Atari where the OS was baked right into the ROM, so you couldn't even change it unless you booted a different OS from a floppy disk.

Secondly, saying that buying a 650W power supply is just throwing money away is complete nonsense. If I personally HAD to buy a unit like that just to get my system to finally stop choking and actually breathe with these components, then I'll say it straight—watch your step, because you might just trip and break your neck.

All those online wattage calculators? They basically tell you to take the results with a grain of salt.

Even these threads claiming a 400W unit is plenty... well, sure, it's plenty if you're running a card from five years ago in a rig with a third of the RAM, a tiny 20GB hard drive, and an old CD-RW drive, or whatever.

Oh, so that's how we're playing it...

I’ll give you my resume, then you can decide for yourself just how qualified I am to be giving advice.

I've been working in electrical engineering for about 17 years now. I graduated from one of the most rigorous technical high schools in Washington, D.C., and breezed through electrical engineering courses at two different universities—with a third one in the works.

I have built a mountain of amplifiers, rectifier circuits, oscillators, filters, and testing equipment. Honestly, I've had countless AC/DC power supplies pass through my hands.

I've written enough seminars, scientific papers, and electronic circuit exercises to probably fill an entire spindle of DVDs.

One look inside almost any power supply, and I can tell you pretty much exactly what its output capabilities are.

Personally, I feel like I've only mastered about 10% of what there is to learn about power supplies.

So, how much do you think you actually know?

Good grief, man... being this wrong and still doubling down on it... I almost have to respect the sheer audacity 🙏
If I told you that I used to run dual GTX 275s, a Phenom II X4 clocked at 3.8GHz, two hard drives, five fans, and a whole mess of other gear on a mere 535W power supply—with just 36A on the 12V rail, no less—you’d probably tell me I’m delusional and insist I need at least an 850W unit just to stay afloat. But hey... it worked..
So please, for the love of everything, try to hold back on the arguing until you actually take a second to look up how much power modern components actually pull.
Here is a decent little starting point for you;
http://forum.pcekspert.com/showthread.php?t=189774

Just a quick heads-up: those numbers Zachary Wilson30 posted in the link above represent the AC draw from the wall. Since the power supply itself delivers about 15% less power to the actual components, you’ll need to multiply them by roughly 0.85 to figure out the true DC consumption.

What is this, some kind of retirement home? I've spent 20 years in IT, he's put in 17... where does that leave me? 😁

I have to admit, Morgan Moore37 really shook me up. It actually made me question my entire career and everything I thought I knew... Was Atari the first computer to have actual Windows? Dammit, I must be getting senile, because I have zero memory of that... I know Windows 1.0 came on two 5.25" floppy disks with 360k capacity... but those were for the PC...

And Atari had GEMDOS and TOS later on...

So, you see, Gemdos was basically the ancestor of the OS Microsoft builds their Windows versions on. Those were essentially the very first Windows interfaces.

Back when Atari had those windowed systems, the modern PC didn't even exist yet.
If you strip away all the windows, you can see the foundation of the desktop we use today. Instead of having to type out commands manually, you could just click on icons to open things.

In that era, the big players were Atari, ZX Spectrum, and similar machines, while gaming consoles were what everyone was really obsessed with.

I honestly think Morgan Moore37 has just been talking out of his backside three or four times already. He's probably about 15 years old, reading nonsense online and trying to act like an expert. It’s pretty funny how someone claiming to have 20 years in IT actually knows less than I do after just three years in the field. 🤣

🙂

I doubt there's any point in continuing this argument. 😬 Besides, how did we even get from discussing power supplies to talking about operating systems?