Samsung DDR333 PC2700 Question

I bought a 512meg stick of double sided Samsung from newegg and am wondering if I will have trouble adding two more sticks to up the ram on this system to 1.5gigs...I have these parts so far, Plus1080 Antec case with the Antec 430 PSU, Soltek SL-75DRV5 motherboard, 80gig Maxtor Quiet Drive ATA/133 hard drive, Pioneer 106S DVD-CDROM, Plextor 40x CDRW, SoundBlaster Audigy Platinum, Sony 1.44mb floppy, Windows 2000 as the OS and the above mentioned memory...Still need to decide on the processor (think I will just by the 1.8GHZ retail version XP) or the video card (ATI Radeon 8500DV All-In-Wonder)
Any comments on this box would be greatly appreciated as this will be my first attempt at building something besides your "run of the mill" box and do not want to run into a bunch of hardware conflicts...Thanks !!!

The more memory you add the harder it's going to be to run as high of a fsb. If memory amount is more important to you than fsb speed then 3x512 will work in that board at what speed stable I do not have any idea. If you knew from the start that you wanted that much memory you should have got all ecc as that board supports it.

Not sure what you want to use the sytem for but most people find 512mb is enough.