I have been looking high and low for this issue to have been resolved, but no one else seems to have it. I am using Slack 10 with the default kernel and am trying to upgrade to 2.6.7 but I keep running into a problem.

Every time a boot a kernel other than the default (this includes 2.4 kernels) the system is around 5 times slower! The bootup takes longer, my programs take many times longer to load, and my x server (x.org) is using 3 times the cpu than it should. De-optimizing from athlon to i386 with generic kernel optimizations helps a little.

This happened with Slack 9.1 with the xfree86 server as well.

Does anyone has any ideas on what could be causing this?

X.org TOP readings:
Default kernel : 0.3 - 0.7 cpu
Any new kernel : 1.5 - 3.8 cpu

Glxgears:
Default kernel : 290 - 360 fps
Any new kernel : 50 - 90 fps (no hardware acceleration or DRM on either)

Hardware:
Soyo Via KT400 dragon ultra (onboard sound and 10/100 ethernet)
512M pc2700 ddr ram
AMD athlon 2500+
Excalibur Radean 9600 Pro (the Powered by ATi type)

what hardware are you running? there may be incompatibilities, or its possible you arent compiling in some necessary drivers or features (chipset, etc).

My hardware is listed at the bottom of my first post.

Have you removed any unnessacary modules? If you are using modules try setting them to regular components. I am running a similar setup as far as hardware goes and use no modules in my Kernel 2.6.7.

Unneeded modules? I thought that as long as they are not loaded they don't cause slowdown. I have run the new kernel without any modules loaded (but still compiled and readied to be modprobed) and it doesn't help.

By unneeded modules I meen any hardware drivers that come with the kernel. I.E. do not install Nvidia Driver since don't have an Nvidia card. Even thou the drivers are not in use by the system the kernel is much larger with them in there.

As far as graphics hardware and buses go, its pretty minimal (im wondering if i should use the kernels agpgart for the Radeon with the ATi driver) but I skimmed over the filesystems section, a lot of unnecesary stuff is compiled in there. I don't think thats it though.

Its worth a shot. Use the agpgart for any AGP video card that is fully supported BTW. I would remove any unnessacy stuff from the kernel just so it is more compact. It wouldn't hurt to try it.

Gah, didn't help. Anyway, Im going to be using ATi's proprietary drivers and I think that you should use their agpgart. I know that you supposed to use their DRI.