Hello! Need your help! 3 days ago I bought iMac late 2013 with new generation PCIe Samsung XP941 M.2 based SSD 256Gb. Really powerful SSD. But of course, I was scared about SSD rewrite cycles and wanted to check it because want to keep this computer for 5 years. Found Mac OS X app called DriveDx that can check SSD and HDD lifetime and other S.M.A.R.T. attributes . Utility log here: SSD Lifetime Left Indicator : GOOD 95.0% === SSD HEALTH INDICATORS === ID NAME RAW VALUE STATUS 5 Retired Block Count 0 100% OK 173 Wear Leveling Count 0x100990005 95.0% OK 174 Unexpected Power Loss Count 0xA368E 99.0% OK 192 Unsafe Shutdown Count 6 99.0% OK 197 Current Pending Sectors Count 0 100% OK 199 UDMA CRC Error Count 0 100% OK I used this Mac for 3 days. I just did clean install OS X , installed 80 GB of soft on it, and installed Windows in the second partition and 95% of wear leveling count?! My SSD has 2 partition: Mac OS X (133 GB) and second for Windows 8.1 (117 GB) I know that OS X is very optimized to SSD, but I have second Windows partition and dont know how two systems will live together. Need Windows ONLY for gaming. I have two question. First: I heard that rewrite cycles depends on SSD size. Is it true that my drive turned into two 128 Gb SSD? When one of OS reach 128 Gb then it will rewrite cells again. Right? And lifetime will be a half of 256 Gb. And how about TRIM with two different systems. Is it working correctly? Second: I have an idea how to reduce read/write on Windows. Want to make 30Gb partition for Windows and install all games in my external HDD USB 3.0. Yeah, game loading will be slower, but less read/write gaming data. But this method is useless if external HDD use system SSD as temp storage between RAM and HDD. Does Windows use system drive to store some temporary data between system drive and external HDD or it has direct route to RAM from HDD? If it does, using external HDD is useless, because all temp data will be passing through system SSD and make rewrite.