I've decided to install Windows 7 and try to run my software on it. I have one quad code machine (T7400) and one two quad code R5400, both Dell and I don't feel my Vista Ult utilized the advantage of multicore processors. I can of course improve my software by delegating some taks to separate threads but it is a lot of work. I am hoping that the situation will improve with new OS. So what is the difference between the two downloads? I am aiming for a 64 bit system. Thanks. AlexB

Hi AlexUnless you are an IT Professional or Developer, you don't want to use the Checked/Debug build. The checked build contains fewer optimizations and more debugging checks than the free build, the checked build is both larger in size and slower to execute than the free build. As a result, the free build is used in production environments unless it is necessary to use the checked build to identify serious problems.Hope this helps.Thank You for testing Windows 7 Beta Ronnie Vernon MVP

Hi Ronnie, Checked build is actually smaller. For free buildthe x64 version is 3,320.10 and Checked build is 3,037.25MB. Yes, I am a developer but I don't do much OS development thus it is better for me to avoid using Checked build. It is good I posted because I was about to download the Checked a minute ago. So, the message is: if I run into a serious problem for debug perposes I will have to download Checked, correct? AlexB

AlexBB said: Hi Ronnie, Checked build is actually smaller. For free buildthe x64 version is 3,320.10 and Checked build is 3,037.25MB. Yes, I am a developer but I don't do much OS development thus it is better for me to avoid using Checked build. It is good I posted because I was about to download the Checked a minute ago. So, the message is: if I run into a serious problem for debug perposes I will have to download Checked, correct? AlexB Hi Alex You might want to keep a copy of the checked build handy, if you wish. The only people I know that actually make use of this build are hardwaredriver developers. It really runs like molasses. :)) There is a more complete description here: Checked Build of Windows Hope this helps. Thank You for testing Windows 7 Beta Ronnie Vernon MVP