memtest86's no show

[Albretch Mueller <lbrtchx@gmail.com>]

~
 Probably one of you have managed to run memtest86 on a 64-bit Intel
box (hp-xw6600)
~
 I downloaded and burned memtest86 Version 4.0b (Server) (26-Oct-2011)
onto a CD, but when I boot up the box from the CD all I see is:
~
   Memtest86 Version 4.0b Server
   -----------------------------

   Select Version:

   1) Boot V4.0b Server (Default)

   2) Boot V4.0a

   3) Boot V3.5b

boot: 1
Loading memtest.....ready.
~
 I don't see any progress screen or anything. Running "cat
/proc/cpuinfo | grep flag"
~
 flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov
pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe lm
constant_tsc pebs bts pni dtes64 monitor ds_cpl cid cx16 xtpr lahf_lm
~
 so it handles Long Mode (lm) (64-bit) and the installed memory:
"dmidecode --type memory" show to me 2 DMI types. Two of which look
like:
~
# dmidecode 2.9
SMBIOS 2.5 present.

Handle 0x0036, DMI type 16, 15 bytes
Physical Memory Array
	Location: System Board Or Motherboard
	Use: System Memory
	Error Correction Type: Multi-bit ECC
	Maximum Capacity: 64 GB
	Error Information Handle: Not Provided
	Number Of Devices: 8
~
 and the other ones like:
~
Handle 0x0038, DMI type 17, 27 bytes
Memory Device
	Array Handle: 0x0036
	Error Information Handle: Not Provided
	Total Width: 72 bits
	Data Width: 64 bits
	Size: 4096 MB
	Form Factor: FB-DIMM
	Set: 1
	Locator: DIMM01
	Bank Locator: Not Specified
	Type: DDR2 FB-DIMM
	Type Detail: Synchronous
	Speed: 667 MHz (1.5 ns)
	Manufacturer: JEDEC ID:98 04 08 28 01 12 2F A4
	Serial Number: A42F1201
	Asset Tag: Not Specified
	Part Number:
~
 The version of memtest with knoppix apparently is the 32 bit one
(same with Ubuntu, which does not seem to have a 64-bit version for
AMD software)
~
 why is memtest not working? How can I make it run on my box?
~
 thanks
 lbrtchx