i've got exactly the same problem on a Compaq Deskpro EN 6400/6.4.
It must be a Compaq BIOS problem?
I have already noticed this qeury on linuxquestions.org, but there was not an answer to this.
I try booting Knoppix from CD on my Compaq Armada 7400 laptop, but not successful, the CD is found, SYSLINUX is started, but then boot process halts (I can see the message SYSLINUX DEBIAN 2.04 (Debian, 2003-06-06) followed by a bunch of garbage symbols). When I boot Knoppix from diskette using the same CD, the system loads without any problem. Another hint is that I can boot the system from the same CD on another laptop Compaq Evo N600c.
Appreciate every advice.
i've got exactly the same problem on a Compaq Deskpro EN 6400/6.4.
It must be a Compaq BIOS problem?
Grandstream GS-HT802 2 Port Analog Telephone Adapter VoIP Phone & Device, Black
$32.00
NEW Polycom VVX 501 VoIP IP Phone & Stand Tested VVX501 2200-48500-019 Lync
$43.98
Grandstream HT801 Single-Port Analog Telephone Adapter
$34.00
Cisco IP Phone 7911 CP-7911G VoIP Business Display Desktop Phone 7900 SERIES
$30.00
Cisco CP-7945G VOIP Phone With Stand & Handset Business IP Phone 7945
$3.00
New Cisco 7945G IP VoIP Gigabit GIGE Telephone Phone CP-7945G -
$24.95
Yealink SIP-T54W W/ HD Display Business VoIP Phone w/ Built-in Bluetooth and POE
$69.99
Poly CCX 700 IP Phone OpenSIP - VoIP Phone (2200-49750-025)
$189.98
Polycom VVX 411 VoIP IP Phone & Stand Tested Reset VVX411 2201-48450-001
$19.98
REF A-STOCK - Polycom 2200-48450-025 VVX 411 IP VOIP POE Gigabit Telephone
$39.56