Using memory with different timings/voltages

[buckman341]

This is my current memory

2x1GB
ddr2 800 with 4-4-4-12 timings and 2.1V
Newegg.com - CORSAIR XMS2 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory - Desktop Memory

I want to upgrade for more memory and I'm wondering if I really need to get something with the same timings and voltages to match what I currently have. I was thinking about:

2x2GB
ddr2 800 with 5-5-5-18 timings and 1.9V
Newegg.com - CORSAIR 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory - Desktop Memory

Can I run those at the same time or would I have to just junk the old 2 dimms for these?

If I got something like

2x2GB
ddr2 800 with 4-4-4-12 timings and 2.1V
Newegg.com - CORSAIR XMS2 DHX 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory - Desktop Memory

would I be able to stick with the old dimms for 6GB total?

Thanks.

 

[Hefemeister]

What operating system are you running? --hopes for vista 64bit

 

[buckman341]

nope Using windows XP still...

 

[Hefemeister]

Well that will narrows down your choice a bit. XP 32bit can only use up to 3.25GB of RAM So either combo you get you could only run the 2 giving you 4GB with 3.25GB usable by the system.

 

[buckman341]

Hmm that really blows. That wasn't even updated with any of the service packs? Maybe it's time to update to vista

 

[Hefemeister]

If you want to run that much ram yes but make sure it is the 64bit version.

 

[saltynay]

If your student or have access to a students email you can order it for $70 and ultimate edition

 

[veedubfreak]

If your student or have access to a students email you can order it for $70 and ultimate edition

Heck, vista home premium oem only costs 90 anyway.

 

[saltynay]

yes but thats $20 more expensive and not as functional (admittedly a home user generally wouldn't use the added business bits) but its also comes as a (product) red so guves money to charity.

 

[buckman341]

What's the main difference between a copy of windows xp with service pack 3 and a copy of xp 64 bit ?? I've heard that finding drivers for xp64 can be a real ***** of a job. What about drivers for Vista?

Heard a lot of bad things about Vista, do many issues still linger?