Sinrace Power Supply Technology (Shenzhen) Co., Ltd.

Any time the switchmode transistor requires replacement, check all semiconductors for shorts and fusable resistors for opens. even if you locate what is thought to be the problem early on. Multiple parts often fail and just replacing the transistor may cause it to fail as a result of something else still being bad. In particular, check primary side electrolytic capacitors for reduced capacity or opens. These conditions can result in a blown switchmode transistor as it attempt to supply adequate current during the troughs of the rectified high voltage DC. It only takes a few more minutes. For other problems like an open startup resistor this excessive caution is unnecessary as these are usually isolated failures.

However, if any dried up electrolytics are found, it is good practice to test them all - or just replace them all since the cost and time will be minimal. As they say, 'peas in a pod fail at nearly the same time'.
It is often helpful to trace the circuit by hand if a service manual is not available. You will gain a better understanding of this supply and be able to put the knowledge to use when the next one shows up on your bench - there is a lot of similarity even between different manufacturers. A bright light behind the circuit board may help to make the foil runs and jumpers more visible. The only difficult part will be determining how the transformer windings are hooked up. An ohmmeter will help but even if you cannot entirely determine this, just make a note. For most purposes, the exact topology of the windings is not critical for diagnostic procedures.