I'm using the same chipset and it works fine with the default
xf86config options.
Just enusure in the configuration program, that you have enough ram,
when asking for video-ram. Say you have 64M  and it will work
1280x1024.

If it still does not work, I can post my XFConfig86 file.

Cheers, Zafer.



2006/10/5, Stefanus Hermawan <x11.i386@gmail.com>:
> Hello all,
>
>
> I have installed NetBSD 3.0 on IBM NetVista (i386) with vga chipset Intel
> 82815 (i815).
> I used i810 driver on XF86Config and monitor Samsung SyncMaster 591s (max
> res 1024x768).
> But my maximum resolution only 800x600 (I have tested with slackware and
> ubuntu and get resolution 1024x768).
> Perhaps I have a mistake when setup my X configuration.
>
> Thanks for your help.
>
>
> Regards
>
> ST. Hermawan