MSI 645E Max2-LRU Motherboard Layout
As with all Pentium 4 motherboards, the 645E Max2-LRU requires the use of an ATX 2.03-compliant power supply with a 12V connector. The ATX power connector is extremely well positioned, being directly on the right-edge of the motherboard. This allows easy installation of the power cord, as well as providing excellent airflow over the CPU. The 12-volt connector naturally must be in close proximity to the CPU, though its positioning near the top-left of the board could have been better. In our reference full tower, this was not a problem, though with smaller cases, it may require threading the 12V cord over the CPU.
The CPU socket is positioned quite well, and there is ample room between it and the DDR sockets. Even the other side, with its line of capacitors, has a nice design and there are no obstructions to the actual Socket 478 heat-sink fan (HSF) clips. This lets standard HSF units be installed or removed quite easily. As is becoming quite common these days, the SiS 645DX Northbridge features only a basic heatsink, thereby lowering the ambient noise that a cooling fan would present. The three DDR sockets are very easy to work with, and although it is a tight squeeze, memory can be installed or removed with an AGP card present.
The two standard IDE connectors are in their usual spot, right next to the DIMM sockets, and MSI has positioned the extra IDE RAID connectors horizontally at the bottom of the board. This is pretty standard with RAID motherboards, but the locations of the floppy connector can be problematic, as it is also at the bottom of the board, right above the RAID connectors. In most cases, this will be a non-issue but with very large towers (especially those with the floppy directly at the top of the case) it may present a logistical nightmare to connect. Thankfully the floppy cable included with the 645E Max2-LRU is of the longish variety and worked on all our reference cases, even the tower units.
In terms of cooling fan headers, the 645E Max2-LRU only includes two: a CPU Fan and a System Fan header. While we recommend using the PSU for any significant fan usage, usually a small case fan isn't a big power risk. The only issue with the MSI design is that you're pretty well locked into a front-mounted fan, as per the System Fan header's location.
The ATX back panel is pretty standard fare, noting that the LAN versions of the 645E Max2 include a RJ-45 jack right above the two USB ports. The on-board USB and audio ports are positioned well, and are mostly at the outer edge of the board PCB and well out of the way of AGP and PCI cards. The board itself is a bit wider than standard ATX, though not as wide as a full-sized board. This results in a slight overhang, as the screw holes are a good 2.5 inches from the edge of the PCB.