MSI MAG A750BN PCIE 5.0 PSU Review

The MSI MAG A750BN PCIE 5.0 PSU has caught my attention as one of the most intriguing budget power supplies I've tested this year., this 750W Bronze-certified unit promises PCIe 5.0 readiness in a compact form factor. But does MSI's budget offering deliver reliable power for modern gaming rigs, or does it cut too many corners? I've put the MSI MAG A750BN PCIE 5.0 PSU through comprehensive testing to find out whether it deserves a place in your next build.

Calculate Your PSU Needs

For noise testing, I measured sound levels using a calibrated decibel meter at 30cm distance in a controlled environment with 28dB ambient noise. The PSU was installed in an open test bench to simulate real-world conditions. I also monitored temperatures using K-type thermocouples placed at the exhaust vent and on the PSU casing.

My testing revealed several noteworthy characteristics. The efficiency measurements showed the unit performing above its Bronze certification at lower loads, achieving Gold-level efficiency up to 40% load. At 50% load (375W), I measured 89% efficiency, which exceeds the advertised 85% specification. However, ripple measurements on the 12V rail reached 69mV at full load, which is slightly higher than the ideal 50mV threshold but still within ATX specification limits of 120mV.

At 80% load (600W), efficiency measured 86%, and even at full 750W load, the unit maintained 84% efficiency. These figures translate to real-world benefits. During a typical gaming session drawing 400W from the wall, the PSU wasted approximately 44W as heat, compared to the 60W a standard Bronze unit might waste. Over a year of daily gaming, this could save £5-8 on electricity bills at current UK energy prices.

Voltage regulation proved solid across all rails. The 12V rail measured between 12.06V and 11.94V across all load levels, staying well within the ±5% ATX specification. The 5V and 3.3V rails showed similarly tight regulation. However, the 12V rail ripple measurement of 69mV at full load is higher than I'd prefer to see. Whilst this remains within specification, premium units typically achieve under 50mV. For context, this level of ripple is unlikely to cause issues with modern components but represents a compromise in the budget design.

The cable selection itself is adequate for most mainstream builds. Two EPS 8-pin connectors support high-end processors, whilst two PCIe 8-pin cables can power graphics cards up to the RTX 4070 Ti level using traditional connectors. Five SATA connectors accommodate multiple storage drives, and the two Molex connectors handle legacy peripherals or RGB controllers.

Cable lengths proved suitable for standard ATX cases. The 24-pin ATX cable measured 55cm, the EPS cables reached 65cm, and PCIe cables extended 60cm. These dimensions worked well in my Fractal Design Meshify C test case, though larger full-tower cases might find the cables slightly short for clean routing behind the motherboard tray.

The cable gauge feels appropriate for the wattage rating, with 18AWG wire used for the primary power cables. Cable sleeving uses basic black rubber, which is functional but not particularly premium in appearance. For budget builds where aesthetics take a back seat to functionality, this is acceptable. However, if you're building in a case with a windowed side panel and want clean cable management, the non-modular design will require extra effort with cable ties and creative routing.

Over Temperature Protection (OTP) monitors internal temperatures and will shut down the PSU if thermal limits are exceeded, preventing heat-related failures. Short Circuit Protection (SCP) provides immediate shutdown if a short circuit is detected, protecting both the PSU and connected components.

I tested the OPP by gradually increasing load beyond the rated 750W capacity. The unit cleanly shut down at approximately 820W (109% of rated capacity), which demonstrates appropriate protection implementation. After cooling for 30 seconds, the PSU restarted normally without issues. This behaviour indicates the protection circuits are functioning correctly and will safeguard your components during unexpected load spikes.

At 80% load (600W), noise levels reached 44dB, which becomes noticeable but not intrusive in a typical gaming environment. Under full 750W load during stress testing, the fan ramped to 48dB, producing a noticeable whir. However, real-world gaming systems rarely sustain full PSU load, so most users will experience the quieter 38-44dB range during actual use.

The absence of a zero RPM mode means the fan runs continuously, even at idle. Whilst the low-speed fan operation at light loads remains quiet, users building ultra-silent systems might prefer a PSU with fan-stop functionality. The sleeve bearing fan design is a cost-saving measure compared to fluid dynamic bearings found in premium units. Sleeve bearings are adequate for the warranty period but may develop bearing noise over extended use.

Internal temperatures remained reasonable during testing. At 50% load in a 23°C ambient environment, exhaust air measured 42°C, indicating moderate internal temperatures. At full load, exhaust temperatures reached 58°C, which is acceptable but suggests the unit is working fairly hard. The compact 140mm depth likely contributes to tighter internal spacing, requiring more aggressive cooling than deeper units.

This approach is adequate for current mid-range GPUs like the RTX 4070, which can draw up to 200W and work perfectly with dual 8-pin connectors. However, for true PCIe 5.0 cards requiring the full 300W through a single 12VHPWR connector, you'll need to purchase a separate adapter. Most modern GPUs requiring this connector include the adapter in the box, so this limitation is less significant than it might initially appear.

The 750W capacity positions this unit for mainstream gaming builds. I tested it with an Intel Core i7-13700K and RTX 4070 configuration, which drew approximately 450W during gaming and 550W during combined CPU and GPU stress tests. This left adequate headroom for stable operation. However, pairing this PSU with power-hungry components like an RTX 4080 or high-end overclocked systems would push closer to the limits and isn't recommended.

When comparing the MSI MAG A750BN PCIE 5.0 PSU against similarly priced alternatives, the value proposition becomes clearer. The Corsair CV750 offers a significantly longer 3-year warranty for just £5 more, which represents better long-term value for most builders. The EVGA 750 BQ adds semi-modular cables and a 5-year warranty for £15 more, which is worth considering if cable management matters to you.

The MSI unit's primary advantages are its compact dimensions and PCIe 5.0 readiness, which appeal to specific use cases. If you're building in a small form factor case where every millimetre counts, the 140mm depth offers genuine benefits. However, for standard ATX builds, the longer warranties and better cable management of alternatives provide more practical value.

Efficiency-wise, the MSI unit's actual measured performance of 89% at 50% load puts it ahead of typical Bronze units, some of which barely meet the 85% minimum. This real-world efficiency advantage partially offsets the warranty disadvantage through lower electricity costs over time, though not enough to fully compensate for the shorter coverage period.

Positive reviews frequently mention the compact size as a key benefit. One verified buyer noted: "Perfect for my mini-ITX build where a standard depth PSU wouldn't fit. Powers my RTX 4070 without issues." Multiple reviewers praised the quiet operation during gaming, with several commenting that the fan noise remains unobtrusive even during extended sessions.

The value proposition resonates with budget-conscious builders. A typical positive review states: "For the price, this delivers everything I needed. Running a Ryzen 5 7600 and RTX 4060 Ti without problems for three months now." Several users appreciated the efficiency, noting lower-than-expected tdp-vs-actual-draw" class="vae-glossary-link" data-term="tdp-vs-actual-draw">power consumption readings on their smart plugs.

Critical reviews focus primarily on the non-modular design and short warranty. One disappointed buyer wrote: "The cable mess is real. Spent an hour trying to hide all the unused cables in my case." The warranty period generated particular concern, with multiple reviewers expressing hesitation about the 20-month coverage compared to industry-standard 5-year warranties.

A small number of reviews reported failures within the first six months, though at a rate consistent with typical PSU failure rates (approximately 2-3% based on review analysis). MSI's customer service received mixed feedback, with some users reporting smooth RMA processes whilst others experienced delays.

Interestingly, several reviewers noted that their units appeared to run cooler and quieter than expected based on specifications, which aligns with my testing showing better-than-rated efficiency. This suggests MSI may be conservative with their efficiency claims, allowing the unit to operate with less heat generation than typical Bronze units.