i guess 333 is out now...... the article is dated but explains it good
Compatiable with the latest Intel P4 and AMD Motherboards...
ABIT--SD7, SD7 Plus
ASUS--P4S333, P4S333-FX
BIOSTAR--M7SXF, M7SXR, M7SXG, M7SX
CHAINTECH--9SID, 9SJD, 9SID1
ECS--L4S5M, L4S5MG, K7S6A
EPoX--4SDA
Gigabyte--GA-8SDX3, GA-8SRX
Iwill--XP333, XP333-R (ALi MAGiK 1 M1647 C-version)
JETWAY--S445R, S445
MSI--M6547, M6559, M6524, M6558
SOYO--P4S Dragon Ultra
*Also work in AMD platform motherboards which use SIS740/745, VIA P4X266, ALi MAGiK 1 & Intel P4 845D, SIS645/650 chipsets.
*This high quality memory is compatible with all computers using DDR standard, but is not backward-compatible with SDRAM such as PC66, PC100, PC133, PC150, and requires motherboards and systems especially designed for DDR266 and DDR333.