Hardware upgrade
 

This moment I have a rather antiquated computer:
- EPOX 8KTA3 mobo with VIA chipset
- AMD Thunderbird-processor with unbelievable 900 MHz
- Noname graphics-card with an ATI 128 chip
- 3 IDE-harddisks
- 1 IDE DVD-read/writer
- Self-compiled original kernel 2.6.21 for the hardware now
- and some more

Well, the performance is growing worse and worse nowadays with all that performance-hungry applications, the Windows-world introduces also into the Linux-community.

I intend therefore to improve my 5-year-old hardware with the least cost to an, at this moment, acceptable level.
- New mobo, brand to be decided
- New CPU, AMD or Intel, to be decided, 64 and/or 2 core
- New graphics-card (not a high-performance one for games)
- Additional SATA2-disks
- ...

Question:
When I have replaced the mobo/CPU/graphics-card a.s.o. and I then plug in my 3 IDE-harddisks, /dev/hdc5 is the Linux-startdisk nowadays, will my system start or will it not?
And if not, what I very much fear, how can I than configure the kernel to accept all the new hardware and govern it properly?

I guess that depends on what options you used when you compiled your kernel. Perhaps you could add a stock kernel to the boot menu, they shouldn't have any problems dealing with the new hardware.