To quote, roughly translated: Italian developer Alexander of PS3Mod updated Control Fan Utility to version 1.8.1. See below for the changelog.
CHANGELOG CONTROL FAN UTILITY 1.8.1
Added Payload 4.46
Fixed Minor Bug
Fully translated into Italian
Fixed various problems related to an incorrect display of the language ITA (Thanks Dino05)
Update: Updated to PS3 Fan control utility to Version 1.8.1 Fixed, which works on Habib 4.46. Thanks Estwald (Hermes).
Fixed: works on CFW 4.46 Habib and all CFW.
Stay tuned for more PS3 Hacks and PS3 CFW news, follow us on Twitter and be sure to drop by the PS3 Hacks and PS3 Custom Firmware Forums for the latest PlayStation 3 scene updates and homebrew releases!
I found the freeze's reason on my ps3 with Rogero 4.40 v3 is Control Fan Utility because when I don't open it to background running, my PS3 works perfectly in mM or game playing. So, I'm testing it on Rogero 4.41 v1 which has just released and hope it is great!
i am no expert.. i'd try installin rogero 4.40 v1 apparently rogero hasn't ever made a fw past 1 they are all 4.40.1 etc
the other thing is it sounds like a pre ylod of gpu but in a slim would be rare i guess. since ofw works fine it must be the cfw causing it and i've never heard of it. although all ps3 freeze in games etc every now and then,from my experience anyways... look at bf3 while trying to bring up scoreboard (select) in game.. lol
if its a minor inconvenience i wouldn't worry too much, but if its 5 times a day try different cfw.
I use CF on all of my PS3, it is very good but I have some issue:
My one PS3 2501a some times has freeze in mM, movie or in gaming and my other PS3 2501a's Sound LAG while running CF. But all of them have no issue without running CF. Some other PS3 have no issue while running CF. All my PS3 are on Rogero 4.40v3; mM 4.40 and CF 1.7