Memory upgrade options, Latitude D630

800 MHz RAM (PC2-6400) will make no difference.  The chipset in this model can run RAM at a maximum of 667 MHz, so installing PC6400 is a waste of money -- it'll simply downclock.

You'd need a newer system with a Montevina or later chipset for 800 MHz RAM support.

I doubt that your computer can run win 7 64bit. You must have a 64 bit capable processor. Run the Upgrade Advisor to check. You probably would be better with 32 bit.

For the memory, visit Crucial.com to find out what you can use.

1.  ejn63, is right.  Running PC6400 (800mhz) ram won't give you any performance benefits as it will downclock to 667mhz anyways.  With that said it may not necessarily be a waste of money, because I found that at time, 800mhz ram may be cheaper than 667mhz.  The only thing that I would worry about is the CL.  As 800mhz ram is running  at CL of 6 but 667mhz ram runs at a CL of 5.    I hear that it's impossible to tell the difference so the choice is yours.

2.  Mary G couldn't be more wrong.  First off the T7300 is a 64bit capable processor.  Secondly, Windows 7 does NOT require a 64bit processor anyways.  Lastly, I'm running Windows 7 Ultimate 64bit just fine with your same exact specs w/ the Nvidia Quadro NVS135.  Every tasks run just fine.  I can even play WoW on medium settings with decent frame rates.  And I used to play the first COD:MW on this machine as well.  

Lastly this has nothing to do with your question, but I love my D630.  I am tri-booting Windows 7 Ultimate X64, Mac OS X 10.5.8 and, Ubuntu 10.04.  They all run great.  When I take my laptop out, most people are amazed that I have the ability run all 3 of those OSes.  I just wish that the GPU was upgradable so I could drop a nice gaming card in there.  If that was possible I'd probably do that and put in a the best CPU I could find and this machine would be a beast.

If we are allowed to ask here.  How were you able to boot OSX on the D630?

There are many tutorials out there on how to install OSX on the D630.  Just google "D630  Hackintosh".  However the legality of it is ambiguous. As long as you purchase OSX legally and don't resell it, it shouldn't break any laws. However, it does break the OSX End User License Agreement (EULA). All that really means is that they won't give you any tech support. But they wouldn't have anyways since it's hackintosh.

1.  ejn63, is right.  Running PC6400 (800mhz) ram won't give you any performance benefits as it will downclock to 667mhz anyways.  With that said it may not necessarily be a waste of money, because I found that at time, 800mhz ram may be cheaper than 667mhz.  The only thing that I would worry about is the CL.  As 800mhz ram is running  at CL of 6 but 667mhz ram runs at a CL of 5.    I hear that it's impossible to tell the difference so the choice is yours. 2.  Mary G couldn't be more wrong.  First off the T7300 is a 64bit capable processor.  Secondly, Windows 7 does NOT require a 64bit processor anyways.  Lastly, I'm running Windows 7 Ultimate 64bit just fine with your same exact specs w/ the Nvidia Quadro NVS135.  Every tasks run just fine.  I can even play WoW on medium settings with decent frame rates.  And I used to play the first COD:MW on this machine as well.   Lastly this has nothing to do with your question, but I love my D630.  I am tri-booting Windows 7 Ultimate X64, Mac OS X 10.5.8 and, Ubuntu 10.04.  They all run great.  When I take my laptop out, most people are amazed that I have the ability run all 3 of those OSes.  I just wish that the GPU was upgradable so I could drop a nice gaming card in there.  If that was possible I'd probably do that and put in a the best CPU I could find and this machine would be a beast.