The ASRock Z390 Taichi Review: Jack of All Trades, Master of None

System Performance

Not all motherboards are created equal. On the face of it, they should all perform the same and differ only in the functionality they provide - however, this is not the case. The obvious pointers are power consumption, but also the ability for the manufacturer to optimize USB speed, audio quality (based on audio codec), POST time and latency. This can come down to manufacturing process and prowess, so these are tested.

For Z390 we are running an updated version of our test suite, including OS and CPU cooler. This has some effect on our results.

Power Consumption

Power consumption was tested on the system while in a single ASUS GTX 980 GPU configuration with a wall meter connected to the Thermaltake 1200W power supply. This power supply has ~75% efficiency > 50W, and 90%+ efficiency at 250W, suitable for both idle and multi-GPU loading. This method of power reading allows us to compare the power management of the UEFI and the board to supply components with power under load, and includes typical PSU losses due to efficiency. These are the real world values that consumers may expect from a typical system (minus the monitor) using this motherboard.

While this method for power measurement may not be ideal, and you feel these numbers are not representative due to the high wattage power supply being used (we use the same PSU to remain consistent over a series of reviews, and the fact that some boards on our test bed get tested with three or four high powered GPUs), the important point to take away is the relationship between the numbers. These boards are all under the same conditions, and thus the differences between them should be easy to spot.

Due to a slight variation in testing setups between the Z390 new test bench and the previous one, power was expected to run a little higher due to the use of a beefier 360mm AIO cooler. Thanks to this, the power draw does look a little less desirable but it's nothing to be concerned about.

Non-UEFI POST Time

Different motherboards have different POST sequences before an operating system is initialized. A lot of this is dependent on the board itself, and POST boot time is determined by the controllers on board (and the sequence of how those extras are organized). As part of our testing, we look at the POST Boot Time using a stopwatch. This is the time from pressing the ON button on the computer to when Windows starts loading. (We discount Windows loading as it is highly variable given Windows specific features.)

In regards to POST times, the ASRock Z390 Taichi came in as one of the quickest to boot into Windows with a POST time of just over 16 seconds at default settings. What's even more impressive is that the Taichi managed to beat its Z370 counterpart by more than a second when stripped of LAN and audio controllers.

DPC Latency

Deferred Procedure Call latency is a way in which Windows handles interrupt servicing. In order to wait for a processor to acknowledge the request, the system will queue all interrupt requests by priority. Critical interrupts will be handled as soon as possible, whereas lesser priority requests such as audio will be further down the line. If the audio device requires data, it will have to wait until the request is processed before the buffer is filled.

If the device drivers of higher priority components in a system are poorly implemented, this can cause delays in request scheduling and process time. This can lead to an empty audio buffer and characteristic audible pauses, pops and clicks. The DPC latency checker measures how much time is taken processing DPCs from driver invocation. The lower the value will result in better audio transfer at smaller buffer sizes. Results are measured in microseconds.

Even though none of the boards tested has been optimized for DPC latency, the ASRock Z390 Taichi puts in a good middle of the road showing with a maximum latency of 114 µs. This is just below that in terms of performance to the MSI B60 Gaming Arctic and the not too far behind the predecessor, the Z370 Taichi.