144x is a very bad speed for a flash card
144x is less than ATA33 speed
you want to use a compact flash card that says it supports UDMA5, UDMA6, or UDMA7
its complicated because theres many different speed rating systems at play here:
ATA rating vs UDMA rating vs compact flash speed rating
see my posts here:
http://www.oldschooldaw.com/forums/index.php/topic,5700 :: UDMA speeds
http://www.oldschooldaw.com/forums/index.php/topic,3833 :: using compact flash as a hard drive
heres some guidance on the level of rating you need for your compact flash cards depending on what
speed of an IDE port its connecting to, most people are going to need AT LEAST 440x speed rating for
equal performance to an ATA/66 hard drive,
Ultra ATA/33: 33.3 MBps, use at least 220x
Ultra ATA/66: 66.7 MBps, use at least 440x
Ultra ATA/100: 100 MBps, use at least 660x
Ultra ATA/133: 133 MBps, use at least 880x