PCB Design and Functionality

The mainboard PCB is made of black textolite and looks very strict. Black connectors and heatsinks are hardly noticeable against the black background that is why it is easier to study the PCB layout consulting the PCB layout scheme from time to time.

Let’s start with the top of the PCB, where the processor socket is usually located. There is a Parallel ATA connector in the upper right corner of the PCB provided by an onboard Marvel 88SE6121 controller that is also responsible for two eSATA ports laid out on the mainboard rear panel. Right beneath it there is a 24-pin power supply connector.

Five-phase processor voltage regulator circuitry just like the entire Intel DX38BT mainboard uses common capacitors as well as the new solid-state ones. The power comes to the 8-pin ATX12V connector, the MOSFET transistors are covered with wavy-shaped heatsinks, and at first glance this part of the PCB shouldn’t give us any causes for concern. However, note that capacitors are lining up too close to the processor socket, especially the three top ones. It is quite possible that CPU coolers with broad base may be hard to install, for example, solutions like Scythe Mine or Mugen (Infinity). During our test session we used Zalman CNPS9700 LED, because its base is not too big, however, we still had hard times fastening it to the board.

There are no electronic components on the reverse side of the PCB right beneath the processor Socket LGA775 that can hinder cooler backplate installation or close some of the contacts if the plate is made of metal. However, the pins of the closest capacitors are noticeably far beyond the imaginary line connecting cooler retention holes, these pins did give us hard times during cooler backplate installation. Zalman CNPS9700 LED backplate is made of plastic and we did manage to install it in the long run, but we have to admit that Intel DX38BT mainboard is actually compatible with a limited number of CPU cooling solutions.

There is an LED indicator right next to the 24-pin power connector. It lights up when the boards is powered, which is an important and useful feature. The documentation supplied with the board helped us locate two more diodes near the processor Socket.

LED indicator A signals if the processor voltage regulator got overheated, and the LED indicator B – lights up when the CPU itself gets overheated. CPU temperature is monitored with a built-in thermal diode, however we couldn’t find any mention of the thermal diodes next to MOSFET transistors. We wonder how they determined if overheating takes place? Besides, it could be much more convenient if these two LEDs were a little apart, because both of them are red and when the board is inside the system case you may have hard times figuring out which one is actually lit.