I'm a casual computer user with some extra commuter experience/knowledge. I use my Mac mainly for my work (Digital & DTP). Μy unnatural and pointless "perversion" is to have MANY windows open when I work and exposé - I mean MANY windows! (at least 30+ are REALLY needed in order for me to handle simultaneous CMS sites of mine) For example, Safari reaches +80 in tabs on a daily basis (have even reached at one point 215 tabs!), accompanied by Photoshop, Illustrator, Dreamweaver, Cyberduck, Transmission and iTunes (GOD I LOVE OS X ! ! ! ) Until now I was mostly on the run, needing a notebook. My 2006 17" MBP lived past my expectations. It was a REAL workhorse. Sooner or later, I understood though that I would not be able to go by 2009 and get into 2010 with the same CPU (2.33GHz) , RAM (3GB), Adobe CS (3)/OS X (10.5) and screen estate of the external 20" monitor. For the sake of more proper work unit, I sacrificed my MBP (sold it), laid cash on the side (with great effort) and aimed for the king of the iMacs - The i7! After moths of a hopeless hunting of an i7 unit, I finally managed to literally snatch the last unit from retail seller! After 2 days of nail-biting await, it finally arrived bringing me a wave of happiness and a much needed relief. Unpacking it like crazy, I immediately place it in my work-space, which I of course had set-up according to my iMac. I hardly could forget the 2-year-ago experience I had in front of an 8-core Mac Pro. Thinking I would revive those moments of happiness, I eagerly booted up my i7 and went through the initial set-up (factory-installed SL). I remembered that the first boot was pretty slow, so blaming it to its virginal power-up I rebooted it, expecting now all the core power to push the machine to a "Mach-1 speed" of boot-up. And there was my first unexpected turn-off (yet a minor one, compared to the one that followed) - It took almost 2 minutes to get into Mac OS X (scaring me off to my guts, as it took more than 30 seconds to show the initial white-screen Apple-logo). After a moment of thoughts-flooding, I remembered the classic PRAM issue, so I rebooted resetting it. And there it was! No more than 20 seconds! "Wowwwww" I thought to myself I fiddled around almost childishly, just for the sake of seeing all my actions happening three-times (x3 +) the speed I was used to. So after a good hour of play-time and OS X tweaking & settings session, it was time for my crucial test - The Safari flooding! "Oh yeah " I thought to myself, "Count those tabs and drool endlessly as they multiply by hundreds, you nasty little surfer! " But no, the so much awaited crazy-tabbing session never lived up to my expectations - Heck, it was even worse than my previous Mac! Safari (4.04) could barely reach 60-80 tabs and already started getting the i7 down to its knees!!! (not to talk about the rest of the windows/applications, 'stuttering' in every exposé I made) What A MAJOR turn-off!!! "Wait I minute" I thought. "Let's give it a go from the beginning". So, without having installed anything extra on the Hard Disk, I rebooted, erased the HD and re-installed SL. As soon it finished and came back into OS X (really fast this time again), I immediately did ALL the updates, adding this time Safari 4.05 to its arsenal. Opening it up, reloading those 60-80 tabs is when experienced my COMPLETE turn-off - My i7 was just as sluggish as before! "WHAT THE @#$%&#^ !!!!" I screamed, full of pessimism and terror! I tried this again and again, repairing permissions, resetting Safari, erasing the Safari plist in Preferences, etc. but no matter what I tried, there was NO difference AT ALL Now I'm at desperate point, not knowing what to do! Am I being a noob somehow? Is there any problem with the damn Seagate HD? (something that I don't even dare to imagine, as I wouldn't know when I would ever get back my i7 - My country's Mac service and i7 availability suck hard). Would Safari work up to its expectations if I booted up SL in 64 bit mode? (in which case I'm better off with another 4GB RAM) I don't know I'm running out of ideas and solutions I BEG EVERYBODY reading this, from the bottom of my heart, PLEASE HELP me with any ideas/tips/solutions, as my situation can't get any worse I'm really desperate and feel really helpless!!! ...Than you!