First thinkpad - 2 questions

[Oren]

Hello everyone,
I just purchesd my first x61s today, after using an x60s for few months (got it from work).

I spent few hours on the forum today browsing, read some very interesting stuff, but i steal have 2 questions...

1. If we'll forget about the $ factor,
a. Is it possible to install 800Mhz memory on that machine?
b. Will it work in 800Mhz or only 667?
c. If i can get both for the same price, should i take the 800Mhz?

2. I have 4GB of memory which i want the OS to use.
Thought about Vichsa (Vista in hebrew) x64 but preffer xp.
What are my odds to find drivers for XP X64?

Thank's in advance...

[SHoTTa35]

1a - 800mhz is backwards compatible with 667 so it should work
1b - 800mhz i think will run at 667mhz no matter what. Penryn CPUs run at 800mhz but the RAM will be 667mhz. No worries tho, Penryn is actually 4 x 200mhz while RAM is 2 x 333mhz so it's still faster.
1c - I guess if they were both the same price i'd probably get the 800mhz for later when you want to upgrade your system.

2 - Well drivers for XP x64 are touchy at best and XP x64 isn't like Vista x64 at all. It's a bigger pain than it's worth but Vista x64 is definitely a step in the right direction...

[Oren]

Thanks for the reply.

I'm going for a couple of 2GB OCZ 800Mhz cards.

I work as an IT engineer, so i wont to have XP Pro on the machine.
I guess i'll install Vista ultimate x64 as a second OS, having dual OS's.

Another question, Before i buy Vista X64 ($300 !!!):

1. Does Vista X64 works as fast as xp pro on the X61s?

I dont mind tweaking it, giving up Aero and all the "new" stuff, i need it to work fast....

2. Do i need to get a 64bit version of office 2k7? or just install the regular verion on the Vista 64?

Again, thanks in advance....