I built gentoo-sources-2.6.15-r2 with the exact same config I used for gentoo-sources-2.6.14-r5, saying no to any new drivers (and not compiling for size), and when I boot, my boot time splash (running from an initramfs), fades in /REALLY/ slowly. It takes about 10 seconds, when it normally fades in within 3.
After that, bootup is generally very slow - as if my hard disk and CPU speed were quartered, but it does boot successfully.
Once booted, I log in via qingy, qingy disappears as normal but X never starts - it just hangs. I didn't leave it for more than about a minute because I don't have the time.
I had the same slow bootup problem with 2.6.15-gentoo-r1, but with that version fbsplash did not work at all.
Try this from the Changelog:
*gentoo-sources-2.6.15 (03 Jan 2006)
03 Jan 2006; Daniel Drake <firstname.lastname@example.org> +gentoo-sources-2.6.15.ebuild:
Initial 2.6.15 release. Features the new sky2 (Marvell SysKonnect Yukon-II)
vesafb/vesafb-tng users: Your framebuffer will run SLOOOW
unless you explicitly enable mtrr:3 on the kernel command line. I use (for
vesafb): vga=0x318 video=vesafb:mtrr:3
The excerpt from the ChangeLog explains it all. Please reopen this bug in case adding 'mtrr:3' to your vesafb settings doesn't help.
It solves the slow fbsplash part of the problem, but the nvidia driver incompatibility seems to be another problem. Will find/file another bug.