82845G Datasheet, PDF (59/193 Pages) Intel Corporation – Intel 82845G/82845GL/82845GV Graphics and Memory Controller Hub (GMCH)

Register Description
Notes on Pre-Allocated Memory for Graphics
These Register Bits control the allocation of memory from main memory space for use as graphics
local memory. The memory for TSEG is pre-allocated first and then the graphics local memory is
pre-allocated. An example of this allocation mechanism is:
TOM equals 64 MB,
TSEG selected as 512 KB in size,
Graphics Local Memory selected as 1 MB in size
General System RAM available in system = 62.5 MB
General System RAM Range
00000000h to 03E7FFFFh
TSEG Address Range
03F80000h to 03FFFFFFh
TSEG pre-allocated from
03F80000h to 03FFFFFFh
Graphics Local Memory pre-allocated from 03E80000h to 03F7FFFFh
VGA Memory and I/O Space Decode Priority
1. Integrated Graphics Device (IGD), Device 2.
2. PCI-to-PCI bridge, Device 1.
3. Hub Interface.
Intel^® 82845G/82845GL/82845GV GMCH Datasheet
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