If you have a system with AMD Opteron processor(s), then try running the following program on it:

#include  <stdio.h>

inline void cpuid(unsigned int op, unsigned int *eax, unsigned int
*ebx, unsigned int *ecx, unsigned int *edx)
{
   __asm__("cpuid"
   : "=a" (*eax), "=b" (*ebx), "=c" (*ecx), "=d" (*edx)
   : "a" (op)
   : "cc");
}

int main(void)
{
   unsigned int eax,ebx,ecx,edx;
   unsigned int i=0;
   char array[17];
   char *cp=array;

   cpuid(0x8fffffff, &eax,&ebx,&ecx,&edx);

   for (i = 0; i < 4; i++)
       *cp++ = eax >> (8 * i);
   for (i = 0; i < 4; i++)
       *cp++ = ebx >> (8 * i);
   for (i = 0; i < 4; i++)
       *cp++ = ecx >> (8 * i);
   for (i = 0; i < 4; i++)
       *cp++ = edx >> (8 * i);
   *cp = 0;

   printf ("%s\n", array);
}

It can be easily compiled on Solaris with gcc:

$ /usr/sfw/bin/gcc -o opteron opteron.c

If you PC is still not quiet enough after installing fanless heatsink (like this one), I can recommend you to take a good look at Antec's Phantom 350 fanless power supply. This thing is absolutely silent and can provide up to 350 watts of power. The only source of any substantial noise left in my PC now is the hard drives. Turning on the acoustic mode helps a lot there, but the disks are still spinning :-)