ok, first i will say that my intial problem was blank page and no access to blog/admin etc. i went through the general troubleshooting methods:
-checked for 'spaces' in php
-disabled/removed any/all plugins
-rename folders like 'plugins'
-checked 'functions' files
-stray index.html files in root
-wp-config file checked for correct 'paths'
-safe mode at "0" or off
you name it i tried it.
i then tried a completely new 220.127.116.11 wp install...
did it through ftp and then tried upload zipped file through cpanel.
it appears that this error is isolated to one particular domain and to wp installation only. html files load and show correctly.
i have other domains that have similar and/or exact wp setups.
e.g. same number of plugins, etc. etc.
i can't say 100% it is php related. (maybe 95%)
this affected domain has a wp blog at top domain and one in dir. (and the new wp 'test' blog) all have same exact problem.
when i get the blank page, there is nothing else, no error message or anything. (even though it appears it is a 500 error.)
p.s. hosting tells me it may be 'header' file related and they are to check if there any 'redirect' issues, whatever that means.