DeepCool PX1200G ATX 3.0 Gold Power Supply Review

There are a lot of great PSUs hitting the market recently, what with the recent-ish switch up to the latest PCI Gen 5.0 and ATX 3.0 standards, and with newer CPUs and GPUs using a huge amount of power, we're seeing 1000W+ PSU become the norm again. The latest unit from DeepCool ticks all of these boxes, with the latest standards, and a plentiful 1200W output, making it well-suited for any high-end gaming PC or workstation. Silverstone DA1200R Gold There's no silly RGB here or anything like that, it's just designed to be a powerful power supply that isn't going to break the bank. It's built to handle big power spikes, with an increased hold-up time, and also features the latest PCIe Gen 5 12VHPWR connector to support the latest Nvidia GPUs, and likely many future models, without the need for those awful PSU adaptors. There's also 80 Plus Gold Efficiency, and a switchable hybrid and active fan mode. Features ATX 3.0 Power Supply: The DeepCool PX1200G is a newly designed power supply that meets the latest ATX 3.0 standard. With a dedicated 12VHPWR, 2 EPS, and 3 PCI-e ports, the PX1200G provides stable power for a wide range of components. The Past, Present, and Future: With the ability to provide three times the total GPU and twice the total system power for 0.1 ms, power spikes will never be an issue. The PX1200G will provide stable and consistent power to traditional and next-generation PCs. Reliable Stability: Through the use of a dual main capacitor topology, the PX1200G can keep the hold-up time to ≥ 16ms under full load. PCI-E 5.0 Power Supply Perfected: Equipped with the new PCI-e Gen 5.0 12VHPWR cable, the PX-G provides up to 600W for power-hungry GPUS. Static to dynamic: The PX1200G comes equipped with the option to switch into semi-fanless operation. In hybrid mode, the 135mm FDB fan will dynamically adjust out of its zero RPM state once the system load hits a certain threshold. The glory of gold: 80 Plus Gold certified to ensure 90% efficiency under typical load conditions. Specifications For in-depth features and specifications, please check out the official product page here. Packaging & Accessories The box looks great, with a durable brown box and a white slipcover that has a nice photo of the PSU right on the front. On the back, it's littered with all the technical information you could need. I like the slipcover idea too, it means they can use the same box for different products and only have to reprint a smaller bit of cardboard for the cover. It opens on the top, where you'll find a box for the cables, as well as two layers of foam for the PSU. All of the cables are black with all-black connectors, and all the cables have a flat design, so they'll be nice and easy to route. Also, you get a PSU 24-pin jumper, four screws, and some Velcro straps. A Closer Look This is a nice-looking PSU, I love this huge mesh on the fan, it looks pretty cool, albeit if this was on an open test bench, it's at risk of things falling into it. I can pretty much poke a finger into the fan the gaps are that big. There's a good range of connectors, with five PCIE/CPU connectors, three peripherals, and the motherboard connector. And there's also a 12VHWR in a lovely aqua colour that matches the DeepCool branding colours. There are no branding stickers on the sides, just the tiny DeepCool logo in the corners, which is rare to see, there's often a big sticker on the side of a PSU. Around the back, there's a lot of ventilation, which should obviously be great for overall cooling performance. Much like the 12VHPWR port, the power switch is also in that funky colour. There's also a hybrid fan switch, allowing a zero RPM mode at low loads or temperatures, or just a constant fan. Finally, on the bottom of the PSU, there's the specifications sticker, again, all pretty straightforward stuff. A Closer Look - Internal The fan is the HA13525H12SF-Z, which is pretty much the most commonly used fan in a decent PSU these days, so really can't complain about that, it's 135mm and we know it to be good. The fan is connected to a small daughter board on the PSU interior, which has a standard 3-pin connector, and next to it is a switch for the hybrid fan control, there's even an unused 5-pin RGB connector too, which is likely just used for other models. The interior of this power supply looks great, if somewhat familiar. The picture above is the DeepCool 1200W and the picture below is the Silverstone 1000W I reviewed recently, and largely they look extremely similar, with a change to the capacitors seeming to be the only difference to deal with their different capacities. It being based around the same hardware is not a bad thing though, as this is a really nicely built PSU, with a very good-looking AC line-in and filtering stage, and plenty of shielding where it matters. There are a number of daughterboards on the main motherboard, with some huge contacts and thick gauge wiring that looks much more robust than what I usually see. There's another board behind that, offering up the coils for the 3.3v and 5v conversion. All these vertical boards make it so much easier for airflow throughout the PSU. There are two main bulk capacitors in this power supply, helping it reach the massive 1200W output. They're 420v and 450v rated at 470 uF and 680 uF. All the capacitors are high-quality Japanese capacitors too, which is great to see. There are some mid-size capacitors here too, such as these 16v 2200 uF. Two more on the side, which are 16v 3300 uF. And even on the connector board, there are two longer ones stuffed in there too, which is uncommon, but unfortunately, I cannot see their rating. There are three small aluminium heatsinks in the mid-section too, covering the PFC MOSFETs, and the AC/DC rectifiers. Methodology & Testing At eTeknix we take the power supply testing procedure very seriously and have invested a lot of resources into acquiring the appropriate testing equipment. For all power supply reviews, we test the power supplies with dedicated power supply testing equipment. This means we can get the most accurate results from our testing as opposed to using software benchmarks (such as OCCT) or multi-meter readouts which are broadly inaccurate. Testing Hardware Sunmoon SM-8800 Active Load Tester Stingray DS1M12 USB Oscilloscope Voltcraft DT-10L laser tachometer What the eTeknix Test Procedure Involves Testing each power supply at 20/40/60/80/100% load (with load balanced across all rails) and measuring PFC (power factor correction), efficiency (actual power divided by power "pulled at the wall") which also uses a 50% load test, and voltage regulation (deviance from expected voltages of 3.3/5/12 on the main rails). Measuring ripple with an oscilloscope at 20/40/60/80/100% load. Transient loads taken with an oscilloscope are taken from 0% to 100% on the 12v raid, 3.3v rail, and then both combined. Measuring fan speed after a stabilisation period of five minutes at each loading scenario using the Voltcraft DT-10L laser tachometer and a reflective strip on the fan. Testing each power supply's OPP (Over Power Protection) mechanism and seeing how many watts each power supply can deliver before shutting down. Any deviation from this will be explained per review as appropriate on the respective testing pages, but this methodology page will remain unchanged. Other Things to Consider We recognise that a single 12-volt cable can provide only 6 Amps before overheating (which corrupts voltage regulation and efficiency) so we used an adequate number of cables for each power supply to ensure there is no efficiency loss from poor cable selection. If there is more than one 12VHPWR on a PSU, all will be used to test their combined loads. We use the same time scale and horizontal millivolt scale on our oscilloscope for all ripple tests, that is a 20ms T/DIV (horizontal) and a 0.02 V/DIV (vertical) meaning the scale is from -80mV to +80mV, ATX spec dictates that the 12v rail must fall within 150mv of ripple and the 3.3/5 within 50mv so that scale allows us to include both 150 and 50mV peaks. (Some older PSU reviews use different scales which were later ditched as the visual representation they give is inadequate, in these reviews written measurements are provided only). Deviance is the terminology used to represent the way voltages diverge from the expected values Voltage Regulation To test voltage regulation we load the power supply to five different load scenarios that give an equal spread of load across every single rail. So that means 20% on all rails, 40% on all rails and so on. We then calculate the average deviation of each rail from its expected voltage. Ideally, anything of +/- 2% regulation is seen as a very good result. Power Efficiency Power efficiency is measured by calculating the supplied wattage divided by the wattage drawn at the wall/plug, multiplied by 100 to give a percentage. We then compare that to the particular 80 Plus certification the company claims to see if it meets that. You can see the 80 Plus certifications below, we always test power supplies at 230v. Transient Loads Power Factor Correction Power Factor Correction is the ratio of the real power flowing to the load, to the apparent power in the circuit. PFC aims to make the load circuitry that is power factor corrected appear purely resistive (apparent power equal to real power). In this case, the voltage and current are in phase and the reactive power consumption is zero. The closer the number to one the better as this allows the most efficient delivery of electrical power (Source - Wikipedia). Ripple An oscilloscope can easily measure noise and Ripple. These show how much voltage fluctuation there is on a particular rail. We tested the rail stability of the 3.3-volt, 5-volt and 12-volt rails using an identical time and millivolt scale for all graphs. millivolt ripple is measured by the peak-to-peak size of the voltage curve. The latest ATX 12-volt version 2.3 specifications state that ripple from peak to peak must be no higher than 50 millivolts for the 3.3-volt and 5-volt rails, while the 12-volt rail is allowed up to 120 millivolts peak to peak to stay within specifications. Millivolt figures are stated to the closest increment of 5 given their variability. OPP Power supplies are often quoted as having various protection mechanisms and the most important of these is Over Power Protection. In our testing, we crank up the power draw until the power supply either shuts down (meaning the OPP mechanism is present and working) or blows up (meaning it is either not present or not working). We then note the maximum power consumption before the power supply shut down, or before it blew up. Fan Speed When testing in a power supply laboratory it is difficult to take fan noise readings as the noise from the Sunmoon test equipment and air conditioning corrupts everything. The next best thing in our circumstances was reading off the fan speed with a tachometer to get an idea of the noise. The ambient temperature during testing is held constant at 22 degrees, with 1 degree of variation. Each power supply had a consistent period of 5 minutes to stabilise between each load scenario. In my experience, the following general relationships apply between noise levels and fan speeds, though it can vary greatly between the type of fan used. Below 800 RPM - Inaudible/Silent 800 to 1000 RPM - Barely audible 1000 - 1200 RPM - Audible but still quiet 1200 - 1400 RPM - Moderately noisy 1400 - 1800 RPM - Noisy 1800 - 2000 RPM or above - Intolerable Internal Components This is just an example of what you can expect to see on a PSU interior. Efficiency Efficiency is pretty good, hitting its peak at 40% and a good sweet spot between 60-80% load, which bodes well for gaming as even my RTX 4090 and i7 typically pull 400-600W. PFC is good, but not the best I've seen, again typically hitting its sweet spot from about 60% load upwards. PFC (Power Factor Correction) Voltage Regulation Voltage stability is excellent though, a little hot on the 5VSB but still well within the ideal 3% target. Ripple Now, this is weird, the ripple on this PSU is quite high. Is it so high that I'm worried about it? No, the 12V rail should be under 50mv, and the other rails under 150mv, and they're certainly under that. However, compared to a lot of other units I've tested recently it is certainly noisier. This is something I would like to see them improve on in future revisions. 3.3V 5V 12V 5VSB Over Power Protection and Max Wattage I would have liked to see the OPP push just a little higher, given there are two massive bulk capacitors on the interior, but hey, this is already a 1200W unit, so a 23% bump on that is not insignificant. Transient Loads These results measure the power supply from 0% load to 100% load on various rails to simulate a power spike from your system. Typically, we would like to see as small a spike as possible relative to the requested voltage. With modern GPUs being notorious for power spikes, this is becoming more relevant in modern PSU design. The specifications for ATX 3.0 were released in February 2022. It includes the new 16-Pin 12vHPWR connector that can deliver up to 600 W to graphics cards. These incorporate data lines for components to negotiate power capabilities with the PSU so they do not draw more power than the PSU is capable of delivering. The specification also has more strict requirements for handling spikes, two times the nominal output for 100 microseconds. Transients are looking very good, with a pretty much instant transition for the 3v and 5vsb, a fairly smooth curve up to the 12v load, and more importantly, it doesn't overvolt at any point. 0-100% 3V 0-100% +5VSB 0-100% 12V Cross-Loads 3.3V and 5V are tested at 10-100% loads together, and then 12V is tested in the same fashion. This shows us if the PSU is able to maintain its target voltage regulation while delivering different loads. Ideally, you want to see this within 5% deviance, but under 3% is better, and of course, the lower the better with 0.00% change being the ideal result. Everything is well within that 3% target here, with voltages very consistent in the 3.3v and 5v testing, and while there are some differences with the 12v loaded instead, again, they're nothing to be concerned about and well within tolerances. Fan Speed The fan on this PSU is pretty active, easily spinning faster than most I test, and even the hybrid fan mode didn't make a big difference short of the 20% load. It's 21c in the testing room today too, so it's not like I'm toasting the thing. However, the fan is a good quality FDB 1135mm model, and despite spinning up pretty fast, it seems surprisingly quiet, no louder than a typical case fan, so even at high loads, you're unlikely to be bothered by it over say your CPU or GPU cooler. However, there is still clearly room for improvement, I doubt it needed to spin that fast. How Much Does it Cost? The DeepCool PX1200G ATX 3.0 Gold Power Supply is priced at £179.99 on Amazon, which is actually a fairly decent price given this is a powerful unit, and it has a shorter length than many PSUs of this output at just 160mm, so it'll have impressive compatibility. It's about the same price as similarly equipped models from the likes of Seasonic, Thermaltake and Corsair, so nothing overly surprising to take away from that really. Overview This is an interesting power supply, as it's plenty powerful and can deliver big wattages at a competitive price. However, I just don't think it quite meets the standards set by the competition. This is interesting, as the interior design is clearly mostly identical to that of the Silverstone DA1000R, but with a few capacitors swapped out to deal with the higher wattages. The Silverstone performed a little bit better, but with less noise on the 12v, 3.3v and 5vsb, so I suspect the double capacitor design of the PX1200G is to blame there. While Silverstone ran a similar platform for 1000W, it required very little cooling, with zero RPM fan mode retained until 60% load, and only 876 RPM at maximum load. Meanwhile, the 1200W from Deepcool only worked with a zero RPM fan below 40% load, and the fan was maxing out around 1500-1700 RPM to keep it cool, not that it ran particularly hot, but just seemed to be a little too proactive with its fan curve. The build quality is excellent though, with 100% Japanese capacitors throughout, and the overall construction is fantastic on the interior, with thick gauge wiring, robust-looking solder, and a good overall layout that's beneficial to airflow and cooling. I love that it's fully modular too, and little details like the DeepCool logo colour-matched power button and 12VHPWR connector look pretty cool too. There's no big branding sticker on the side either, which is a nice change from what we usually see, and I like small details like that. Should I Buy One? Overall, this is a very good power supply, and while it does have some higher ripple than the competition on the 12V rail, it's not so high that I think it's cause for concern, but there's still room for improvement regardless. The fan spins a little fast but surprisingly didn't seem all that loud despite the over-active cooling, and the PSU was even that warm anyway. But if you want a compact ATX PSU that can drive big wattages to deal with the 600W 12VHPWR and still have enough juice to power some of the latest flagship CPUs, it's a good choice for a gaming system that you plan to max out on a daily basis.