I'm trying to build a sleeper PC using an upright HP Kayak XM 600 case from around 1999. The case uses a proprietary removable motherboard tray with a grid of square holes and clip-in metal standoffs, but none of the mounting points match the ATX layout on my Gigabyte GA-970A-DS3P motherboard. The case itself is otherwise fairly plain inside. I'm considering mounting the motherboard to an acrylic or custom sheet-metal plate and then attaching that plate to the few usable threaded holes in the case. Is there a specific adapter or better way to handle this?
1 Answer
That removable panel sounds like a proprietary motherboard tray, not a standard ATX mounting surface. Older cases sometimes used slide-out trays with their own clip and hole patterns, so the fact that the case is described as ATX-compatible doesn’t necessarily mean the tray follows the modern ATX mounting layout. There probably isn’t a ready-made adapter for this exact chassis. First remove the original clips and carefully mark the standard ATX hole positions on the tray. If none line up, a custom metal adapter plate is the safest option. Acrylic can work for a temporary or light-duty build, but it may crack around standoffs, flex under the board, and have poorer grounding and heat resistance. Make sure the motherboard has a standoff at every supported mounting point, with no unused standoffs touching the underside, and verify that the rear I/O opening, expansion slots, power supply, graphics card, and cable connections all line up before drilling or cutting.
Yes, it’s definitely the proprietary motherboard tray. It has a Swiss-cheese pattern of square holes for clip-in standoffs, but none of the available positions match the ATX layout on my board. I’ll probably use the existing tray as a mounting point for a custom metal plate rather than relying on acrylic.