sorry my mistake, I was confusing it with something else. In winXP 32bit you can use 3.5 indeed.OK, thats new. Why should i have useless Ram? 32bit Win XP3 works with 3.25, i have 4 because thats the size you buy - 2x2gb.
Unsure how to gather the ram use, i have tune up, the mem optimizer says 2.2 free ram????
to monitor your ram I advice to download process explorer from here (you need an older version of win xp thats why you cant take it from the microsoft site):
Old Version of Process Explorer for Windows XP Download - OldApps.com
after intalling that you can use it to look at your ram usage, it shows a graph over time. so let it run and as soon as you get the CTD check at which point the crash happened.