Tazz <dmswaine@gmail.com> wrote:

<snip>

Hmmm, Avast seems to be running in 32 bit mode. But it's working 
correctly. I have all the Avast services disabled and only use the right 
click context menu "scan file" when I want to check a file out.

As long as it supports the OS is what matters. 
The only "actual" 64bit app I have is Internet Explorer and yes,
there is no flash player for it. I am constantly bombarded
by messages to download flash player. I have to switch to 32bit
Internet Explorer. Fortunately, they share the same "favorites". 

according to 
http://msdn.microsoft.com/en-us/library/aa366778.aspx#physical_memory_limits_windows_xp
Vista business supports up to 128 gigs of ram. I don't know how much 
XP64 supports, but it should be at least 8GB. Unfortunately, my XP64 os is
married to a motherboard that uses expensive DDR, not DDR2, so I haven't
punched through the 4GB barrier yet. Were I able to, even 32bit apps would benefit
from the extra ram. 

Most motherboards have 2 or 4 slots; I have seen some with 8. The largest 
DDR2 DIMM that is readily available is 2GB, so the hardware is limiting us
to 8GB, maybe 16. 

Here is a link to the only 4GB DDR2 DIMM I could find:
http://www.newegg.com/Product/Product.aspx?Item=N82E16820134863
you don't want to know the price.