void clearblock (short *psblock)
{
	_asm
	{
		mov		edx, -16 
		mov		esi, psblock 

		pxor  mm0, mm0 // mm0 = 0x00
lq1:	
		movq	qword ptr [esi], mm0 
		add		esi, 8
		inc		edx
		jnz		lq1
		emms
	}
}