There is no 5.3b...current version is 5.2e and only get it from PhoenixMiner post not any other user posting links.  5.3b is a scammer trying to get you to installl his malware.  Only use links provided by the original author/poster of the mining thread.  If its a new user or a user under 50 posts...just skip it.  Seems there is a scammer amongst us.  So we try to educate like this so you dont get bitten. 

For 4gb cards some (windows) users cant mine now.  Other users (still windows)are seeing major hashing reduction.  After about Christmas then even linux miners wont be able to mine with 4gb...if they do then it will be at huge penalties.