Hi valentin122, you're board does not support PC2700 memory.
The link below will take you to you're board,
MSI 845 UltraC (MS 6566). Suggest you add to you're favorites.
There is not a bios upgrade to support PC2700 memory.
You're manual is here.
See page 2-5 in you're manual.
The mainboard provides 2 slots for 184-pin, 2.5V unbuffered DDR DIMM with 4 memory banks. You can install PC1600/PC2100 DDR SDRAM modules on the DDR DIMM slots (DDR 1~2).
To operate properly, at least one DIMM must be installed.
Here is a link for you're memory. To reach you max GB, you would need 2 DIMMS.
Have more questions, feel free to ask.
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