Thermaltake’s Smart BM2 750W model, offers high performance among affordable 750W power supplies. The company chose Channel Well Technology’s platform to build upon. The semi-modular cable interface will help during the PSU installation, and the fact that this unit achieves Silver in the Cybenetics efficiency rating system shows its platform’s capabilities. Its major opponents are the Corsair CX750 and CX750M, the new XPG Pylon with similar capacity, and the Cooler Master MWE Bronze 750.
Thermaltake’s Smart BM2 line consists of four models with capacities ranging from 450W to 750W. The 750W unit we’re focusing on achieves Bronze on 80 Plus’ scale and Silver in Cybenetics. The output noise is increased, though, achieving Standard+, which means above 35 dBA overall noise output.
Product Photos
Thermaltake equipped this PSU with a rifle bearing fan to survive the five-year warranty. The external design looks nice, thanks to the punched fan grille, though it looks restrictive. Considering that this is not a Gold or Platinum PSU, the fan grille should be less restrictive to allow for higher airflow. Lastly, the PSU’s modular panel only includes six sockets since the 24-pin and a pair of EPS connectors are installed on fixed cables.
Product Photos
Specifications
|
Manufacturer (OEM) |
CWT |
|
Max. DC Output |
750W |
|
Efficiency |
80 PLUS Bronze, Cybenetics Silver (85-87%) |
|
Noise |
Cybenetics Standard + (35-40 dB[A]) |
|
Modular |
✓ (Semi) |
|
Intel C6/C7 Power State Support |
✓ |
|
Operating Temperature (Continuous Full Load) |
0 – 40°C |
|
Over Voltage Protection |
✓ |
|
Under Voltage Protection |
✓ |
|
Over Power Protection |
✓ |
|
Over Current (+12V) Protection |
✓ |
|
Over Temperature Protection |
✓ |
|
Short Circuit Protection |
✓ |
|
Surge Protection |
✓ |
|
Inrush Current Protection |
✓ |
|
Fan Failure Protection |
✗ |
|
No Load Operation |
✓ |
|
Cooling |
140mm Rifle Bearing Fan (TT-1425 DF1402512SEMN) |
| Semi-Passive Operation | ✗ |
| Dimensions (W x H x D) | 150 x 85 x 160mm |
|
Weight |
1.7 kg (3.75 lb) |
| Form Factor |
ATX12V v2.52, EPS 2.92 |
|
Warranty |
5 Years |
Power Specifications
| Rail | 3.3V | 5V | 12V | 5VSB | -12V | |
|---|---|---|---|---|---|---|
| Max. Power | Amps | 20 | 20 | 62.5 | 2.5 | 0.3 |
| Watts | 120 | 750 | 12.5 | 3.6 | ||
| Total Max. Power (W) | 750 | |||||
Cables & Connectors
| Native Cables | ||||
| Description | Cable Count | Connector Count (Total) | Gauge | In Cable Caps |
|---|---|---|---|---|
| ATX connector 20+4 pin (600mm) | 1 | 1 | 18AWG | No |
| 8 pin EPS12V (660mm) / 4+4 pin EPS12V (150mm) | 1 | 1 / 1 | 18AWG | No |
| Modular Cables | ||||
| 6+2 pin PCIe (500mm+150mm) | 2 | 4 | 18AWG | No |
| SATA (500mm+150mm+150mm) | 3 | 9 | 18AWG | No |
| 4-pin Molex (500mm+150mm+150mm+150mm) / FDD (+150mm) | 1 | 4 / 1 | 18-20AWG | No |
| AC Power Cord (1380mm) – C13 coupler | 1 | 1 | 18AWG | – |
The ATX and EPS cables are fixed, but all of the other cables are modular. Our only objection here is that both EPS connectors are on the same cable, so you cannot fully utilize them. On the other hand, someone could argue here that this PSU won’t be used with energy-hungry CPUs.
All of the cables are long and it is good to see an adequate distance between the peripheral connectors. Lastly, there are no in-cable caps, and the flat, fixed and modular cables will block less airflow inside the chassis.
Cable Photos
Component Analysis
We strongly encourage you to have a look at our PSUs 101 article, which provides valuable information about PSUs and their operation, allowing you to better understand the components we’re about to discuss.
| General Information | – |
| Manufacturer (OEM) | CWT |
| PCB Type | Single Sided |
| Primary Side | – |
| Transient Filter | 4x Y caps, 2x X caps, 2x CM chokes, 1x MOV, 1x Power Integrations CAP200DG (Discharge IC) |
| Inrush Protection | NTC Thermistor SCK-1R55 (1.5 Ohm) |
| Bridge Rectifier(s) | 1x GBU1506 (600V, 15A @ 100°C) |
| APFC MOSFETs | 2x Great Power GP28S50G (500V, 28A, Rds(on): 0.125Ohm) |
| APFC Boost Diode | 1x ON Semiconductor FFSP0665A (650V, 6A @ 153°C) |
| Bulk Cap(s) | 1x Nichicon (420V, 390uF, 2,000h @ 105°C, GG) |
| Main Switchers | 2x Great Power GP23S60HX |
| PFC / PWM Combo Controller | Champion CM6800TX & Champion CM03X |
| Topology | Primary side: APFC, Double Forward Secondary side: Semi – Synchronous Rectification (12V) & DC-DC converters (5V & 3.3V) |
| Secondary Side | – |
| +12V | 2x Advanced Power AP6N3R5P (60V, 80A @ 100°C, Rds(on): 3.58mOhm) FETs & 2x PFC PFR40V60CT (60V, 40A @ 100°C) SBRs |
| Driver IC | SyncPower SP6019 |
| 5V & 3.3V | DC-DC Converters: 4x Sync Power SPN3006 (30V, 57A @ 100°C, Rds(on): 5.5mOhm) PWM Controllers: ANPEC APW7159C |
| Filtering Capacitors | Electrolytic: 2x CapXon (2-5,000h @ 105°C, KF), 6x CapXon (2-5,000h @ 105°C, GF), 10x Chengx (2-4,000h @ 105°C, GR), 1x CapXon (5-10,000h @ 105°C, KH) Polymer: 2x APAQ |
| Supervisor IC | IN1S429I-DCG |
| Fan Model | Thermaltake TT-1425 (DF1402512SEHN) (140mm, 12V, 0.60A, Rifle Bearing Fan)? |
| 5VSB Circuit | – |
| Standby PWM Controller | Power Integrations TNY287PG |
Overall Photos
This is CWT’s CSB platform, which uses a double forward topology on the primary side and a semi-synchronous rectification on the secondary side. The minor rails are generated through a pair of DC-DC converters. The caps on the secondary side don’t belong to top-notch manufacturers. We would prefer to see Teapo (not the SC line) or Elite caps, but this period there is not enough stock to cover every OEM, so most manufacturers have to use other, less-known cap brands.
Transient filter
The EMI filter has all of the required components, including a discharge IC and an MOV to protect against voltage surges. This filter does a good job, according to our EMI test results.
There is an NTC thermistor to handle inrush currents. It isn’t supported by a bypass relay and to make matters worse, it has low resistance to do a good job, so inrush currents are quite high, especially with 230V input.
The single bridge rectifier is bolted on a heat sink. We had to detach it to identify it. It can deliver up to 15 Amperes at 100 degrees Celsius, so it will handle the energy requirements of this power supply.
APFC converter
The APFC converter uses a pair of Great Power FETs and a single boost diode. The bulk cap is by Nichicon and its capacity is low, for a 750W power supply. Lastly, the combo PFC/PWM controller is the legendary Champion CM6800, which was widely used a few years ago. It is supported by a CM03X IC.
Main FETs and primary transformer
The pair of main FETs is installed into a half-bridge topology.
12V FETs and VRMs
The 12V rail is regulated by two pairs of FETs and SBRs. This way efficiency takes a hit, but the cost is lower. The minor rails, are generated through a couple of DC-DC converters.
Filtering caps
The electrolytic filtering caps are provided by CapXon and ChengX. Although their specs are good, on paper at least, still we would like to see higher quality caps. Nonetheless, there is a big shortage on Teapo and Elite caps because of the increased demand, so OEMs have to use other cap brands to continue production.
5VSB circuit
A Power Integrations TNY287PG is the standby circuit’s PWM controller.
The supervisor IC is an IN1S429I-DCG, but no further information seems to be available about it other than a model name.
The small modular board is connected to the main PCB through several thick power cables.
Soldering quality
Soldering quality is acceptable. Definitely not the best we have seen by CWT, but this is an affordable platform.
Cooling fan
The cooling fan uses a rifle bearing, according to Thermaltake and I don’t have a reason not to believe it, since the provided warranty is long at five-years. Most plain sleeve bearing fans won’t live as long.
MORE: Best Power Supplies
MORE: How We Test Power Supplies
MORE: All Power Supply Content