Whats memory timing all about ????

I have an amd64 computer, FSB = 400 Mhz (requires DDR PC3200 memory)

i used to have one 512 DDR PC3200 memory module, but bought a second one. (Kingston memory)

when i added the second memory module, the pc became very unstable.
frequently crashing in windows, and reporting constant kernel panicks in linux.

i ran memtest86 on the machine, which confirmed my suspicions, that the new memory module was not functioning correctly.

I returned the module to the shop, they said they needed to test it before replacing it.

they only had a 333Mhz FSB machine to test it on, and the module passed all of there tests (they ran a screen saver, and a defrag in windowsXP)

I left them the module with there technician, to get it tested at full speed on a FSB 400Mhz machine.. (im hoping it fails, otherwise ive wasted £30.

Anyway, one thing i noticed when i added an extra memory, was the bios reportde a different memory timing (it reported 1T where it usually reports 2T)

this setting is automaticallt detected by bios and cannot be altered by users...
the FSB clock was still 200Mhz (effectinve 400mhz thanks to DDR)

and it got me wondering.... what is this 1T timing ???

when they tested the chip, they only put the one memory module in the computer... maybe my computer failed because it had 2 memory modules ?????

thanks

EDIT:
It turned out to be a bios issue,
my motherboard was incorrectly detecting the DRAM latency timing.

Also, the 1T setting is considered unstable, and should only be used if you are over clocking, OR your memeory is rated at higher clock rates than your motherboard.