whenever I enable 3D hardware accl, I get a blank screen and i need to restart and run XFdrake to disable it before I can login to X.
followed instructions on first post of thisthread

now, when I want to run the command /sbin/insmod agpgart it says "agpgrat: no such file or directory" in fglrxconfig option.

I've XFree4.3, kernel 2.6 on mandrake 10 CE. Radeon 9100.
Moreover, on my XF86Config-4 there's no "Load "dri"" line in it, but even when I put it there, it still didnt fix my problem.

I even read the HowTo on rage3d.com but there are still somewhere that I got stucked at.

I got the error "file not found"
my directory is /usr/src/linux-2.6.3-4mdk, i wonder if this is the one i need.
please let me know what other information you need to know to solve my problem.

It sounds like you have it configured to use the external agpgart module. If that's the case, you need to make sure it exists. Try . Also make sure your kernel has support built for your particular chipset.

modprobe -l | grep agpgart
output: /lib/modules/2.6.3-4mdk/kernel/drivers/char/agp/agpgart.ko.gz

Thanks for mentioning about the chipset, now, I think its the problem of it because I have a SiS 648FX.

After searching in google for a while I found that i need to have the following section in agpgart_be.c, which I already have except the line "0x0648". Adding the line dont seem to fix the problem.
{
0x0648,
PCI_VENDOR_ID_SI,
SIS_GENERIC,
"SiS",
"645dx",
}

now, I also find that there are is unofficial patch for my chipset like the one in here . But I just dont know what to do with the codes. I have also searched this forum for a patch for my chipset yet I dont think I found anything yet.