I am going to build a machine for a friend who MUST have a desktop case. The case measures 43cm Wide X 45cm Deep X 14cm High

The spec is going to be:

350 Watt PSU
Soltek SL-75DRV4 Mobo
AMD Athlon XP1800 with AMD retail fan.
256MB PC2100 Memory
64MB Leadtek Winfast Ti4200 Graphics Card
20GB 5400 Hard Disk
52X CDROM Drive
Floppy Drive
Sound Blaster Live! 5.1 Sound Card
56K Modem

I am not planning to overclock it to start but it is a possibilty.

Am I going to have trouble without any extra case fans even without overclocking?

Thanks in advance for you help.

Stuart