start end size type description
Low Memory (the first MiB)
00000000 000003FF 400 (1 KiB) RAM - partially unusable (see above) Real Mode IVT (Interrupt Vector Table)
00000400 000004FF 100 RAM - partially unusable (see above) BDA (BIOS data area)
00000500 00007BFF 7700 (almost 30 KiB) RAM (guaranteed free for use) Conventional memory
00007C00 (typical location) 00007DFF 200 RAM - partially unusable (see above) Your OS BootSector
00007E00 0007FFFF 7FB00 (481 KiB) RAM (guaranteed free for use) Conventional memory
00080000 0009FBFF 1FC00 (approximately 120 KiB) RAM (free for use, if it exists) Conventional memory
0009FC00 (typical location) 0009FFFF 400 RAM (unusable) EBDA (Extended BIOS Data Area)
000A0000 000FFFFF 60000 various (unusable) ROM Area (384 KiB)