Here we go, here they are...
First bunch are with 64 for AGP aparture
First demo is without SBA, normal settings, 32 bit color in 1024x768

Date / Time: 10/3/2003 3:54:43 PM (604218ms)
1700MHz, 512MB, 128M nVidia GeForceFX 5200 (DeviceID=0x0322)
Driver=6.14.10.4523 Shader=1.1
C:\Program Files\Microsoft Games\Halo\Halo.eXe -use11 -timedemo
(Version=1.0.1.580)
Frames=4700
Total Time=295.12s
Average frame rate=15.93fps
Below 5fps= 14% (time) 0% (frames) (42.786s spent in 17 frames)
Below 10fps= 24% (time) 5% (frames)
Below 15fps= 46% (time) 21% (frames)
Below 20fps= 64% (time) 41% (frames)
Below 25fps= 83% (time) 67% (frames)
Below 30fps= 94% (time) 86% (frames)
Below 40fps= 98% (time) 95% (frames)
Below 50fps= 99% (time) 96% (frames)
Below 60fps= 99% (time) 97% (frames)
Memory used Max=166MB, Min=132MB, Ave=153MB

Second demo is with SBA, normal settings, 32 bit color in 1024x768
Date / Time: 10/3/2003 4:02:34 PM (1075078ms)
1700MHz, 512MB, 128M nVidia GeForceFX 5200 (DeviceID=0x0322)
Driver=6.14.10.4523 Shader=1.1
C:\Program Files\Microsoft Games\Halo\Halo.eXe -use11 -timedemo
(Version=1.0.1.580)
Frames=4700
Total Time=294.74s
Average frame rate=15.95fps
Below 5fps= 14% (time) 0% (frames) (43.151s spent in 17 frames)
Below 10fps= 24% (time) 5% (frames)
Below 15fps= 46% (time) 21% (frames)
Below 20fps= 65% (time) 42% (frames)
Below 25fps= 83% (time) 67% (frames)
Below 30fps= 94% (time) 86% (frames)
Below 40fps= 98% (time) 94% (frames)
Below 50fps= 99% (time) 96% (frames)
Below 60fps= 99% (time) 97% (frames)
Memory used Max=165MB, Min=132MB, Ave=153MB
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The following are with 128 for AGP aparture
First demo is without SBA, normal settings, 32 bit color in 1024x768

Date / Time: 10/3/2003 4:13:43 PM (116781ms)
1700MHz, 512MB, 128M nVidia GeForceFX 5200 (DeviceID=0x0322)
Driver=6.14.10.4523 Shader=1.1
C:\Program Files\Microsoft Games\Halo\Halo.eXe -use11 -timedemo
(Version=1.0.1.580)
Frames=4700
Total Time=297.28s
Average frame rate=15.81fps
Below 5fps= 15% (time) 0% (frames) (45.107s spent in 16 frames)
Below 10fps= 24% (time) 5% (frames)
Below 15fps= 46% (time) 22% (frames)
Below 20fps= 65% (time) 41% (frames)
Below 25fps= 83% (time) 67% (frames)
Below 30fps= 94% (time) 86% (frames)
Below 40fps= 98% (time) 94% (frames)
Below 50fps= 99% (time) 96% (frames)
Below 60fps= 99% (time) 97% (frames)
Memory used Max=166MB, Min=132MB, Ave=153MB

Second demo is withSBA, normal settings, 32 bit color in 1024x768
Date / Time: 10/3/2003 4:20:16 PM (516921ms)
1700MHz, 512MB, 128M nVidia GeForceFX 5200 (DeviceID=0x0322)
Driver=6.14.10.4523 Shader=1.1
C:\Program Files\Microsoft Games\Halo\Halo.eXe -use11 -timedemo
(Version=1.0.1.580)
Frames=4700
Total Time=291.42s
Average frame rate=16.13fps
Below 5fps= 13% (time) 0% (frames) (39.399s spent in 15 frames)
Below 10fps= 23% (time) 5% (frames)
Below 15fps= 44% (time) 20% (frames)
Below 20fps= 64% (time) 41% (frames)
Below 25fps= 83% (time) 67% (frames)
Below 30fps= 94% (time) 86% (frames)
Below 40fps= 98% (time) 95% (frames)
Below 50fps= 99% (time) 96% (frames)
Below 60fps= 99% (time) 97% (frames)
Memory used Max=165MB, Min=132MB, Ave=153MB

As you can see there is a noticble difference