I just traded two of my four sticks of Crucial PC2100 256MB for 1 512MB module of Infineon, and the Infineon does PC3200 speeds without a voltage boost! The Crucial won't even reach PC2700 at 2.77 volts. So question is am I better off with 1GB of PC2100 or 512MB of PC3200?
The slowest essential hardware is the Hard Drive. If you understand the conscept of virtual memory, you shoud already know than more memory = less access to harddrive due to page faults. since your hard drive is far slower than ram, increasing amount of ram is going to improve overall system performance.
Faster memory is increases performance because it reduces latency of the transfer of data and instructions to be processed by CPU. In other words the faster CPU can access memory, the less time it would have to wait for data and instructions to be processed, which of course increases performance.
High Speed memory alone will not help. For example if you had only 128 MB of DDR 400. The lack of physical memory would result in more page faults, which means a higher access rate to the hard drive. Of course this renders the highspeed memory usless. Because the cpu must wait for Ram to wait for the hard drive.
My rule of thumb is to double microsofts memory requirements.
Minimum for Win XP is 128 My minimum = 256MB
Recomended for Win XP = 256MB My Recomended is 512MB.
The best solution is to get speed and quantity.
1GB or greater of the fastest ram you board suports is my soulution to memory bottlenecks.