1 × 24-pin ATX main power, 1 × 4-pin ATX 12V power 2. Processor (CPU) Compatibility
If you're looking for additional resources or need to download the MS-7826 motherboard manual, here are a few links to get you started:
For users looking to upgrade, the MS-7826 offers a significant capacity for DDR3 memory. ms-7826 motherboard manual
Populate slots 1 and 3 first for dual-channel operation. Internal Connectors & Layout Guide
Then search HP's support site with that model number → download the (includes motherboard layout, jumper settings, BIOS, etc.). 1 × 24-pin ATX main power, 1 × 4-pin ATX 12V power 2
Popular compatible CPUs: Core i7-4770, i5-4570, and i5-4430.
Power supply or CPU overheating failure. Check that the 4-pin CPU fan header is securely connected to CPU_FAN . Internal Connectors & Layout Guide Then search HP's
The manual explicitly states that the MS-7826 requires a plus a 4-pin CPU power . Using a standard 8-pin EPS12V cable might fit physically but will damage the motherboard unless your PSU splits to 4+4. Do not use adapters without consulting the voltage diagram on page 9.
While the LGA 1155 socket supports many processors (from Celeron to Core i7-3770K), the OEM BIOS on the MS-7826 often restricts TDP (Thermal Design Power) to 77W or 95W. The manual contains the official "Qualified Vendor List" (QVL) for CPUs. Installing a Xeon E3-1275 without checking the manual first will likely result in a black screen.
Connect the Power LED cable. Pin 2 is Positive (+), Pin 4 is Negative (-).
What (graphics card, CPU, or SSD) are you trying to install?