All 1 GB DDR SDRAM modules I've seen usually comprise a strip with 8 chips each side ... and with a space in the middle for a 9th chip.
Recently I found a RAM module that purports to be a DDR400/PC3200, has 8 chips each side BUT no space in the middle!
The unit is from Transcend, so why is this different from a usual DDR strip?
R.