32bit vs 64 bit what other factors you need to consider?

Is 64 bit means more memory? Yes, to be precise.

Microsoft has been investing heavily on X64 bit and within couple of years there will be no more development on 32-bit applications, as per the recent road map.

So within 32-bit application it is one of the reason that memory has been a constraint on scaling-up server capacity. Once you consider that on a Windows system or any application, half of this is reserved for the system address space (aka PAE  with /3GB switch is used in boot.ini) the remaining private address space for each process will get hit even it is a small one to compare, having load on virtual memory. So to answer to this problem of memory addressing is 64-bit computing, which allows much more memory to be addressed. On the other hand a downside is that new servers and a switch to a 64-bit operating systems are required (if not now in future).  As you may have seen 64 bit investment within Windows operating system, SQL Server, Visual Studio applications and so on. A simple table to compare the 32 vs 64 bit resources:

So with this enhancements there is a fight between 2 major chip-makers (not food based) such as Intel & AMD. You may be aware that AMD beat Intel to market last year with 64-bit x86 chips and with dual-core chips, with this Intel has come out with a roll out of 45-nanometer technology, which promises to use less power and generate less heat while delivering greater performance.

That means having 64 bit system means all your problems are solve?

Having higher resources is always helpful and due to the nature of Windows Server that is a complex system and performance is constrained by the component with the lowest performance. So if the problem persists best option is to identify the bottleneck at first going through an issue of memory bandwidth. As memory plays major role in how fast data can be moved to and from memory and written to disks. Then comes to the latency (speed) to cater those data needs, that leads to I/O performance about how much data must be moved by inserting or updating.