1066 5-5-5-15 vs 800 4-4-4-12

Ah, therein lies the question!

The answer is, people will argue about it!

I'm running G.Skill 1066 RAM (technically it's 1100) but it's the perhaps better 1.8-1.9V type. And I'm running it at 4-4-4-10 @ 800, really 820 with slight bus OC.

For a good article of latency vs bandwidth, see Tom's article - especially the conclusions page at the end. This is on DDR3 but all applies to other RAM.
http://www.tomshardware.com/review [...] ,2325.html

For the beginning of a tech discussion I'm having regarding speed vs latency, see this thread:
http://www.tomshardware.com/forum/ [...] nojs=0#bas

I'd say, choose one and be happy with it. Neither choice will make even a 1% difference in 99% of the things you use the computer for. Of course, some would argue that too!

As mentioned in the other thread - I picked the 4-4-4-10 16 because those are the numbers in the SPD for 533 MHz setting. Seemed logical that if it could run 533 at those, then might run 800. It tests out fine.

You might try the same thing, look at your SPD with CPUz and set it to the 267/533 setting. But the difference in Cycle Time of 2 clock ticks? Makes no difference. Note that bilbat has the same RAM as you do and runs it at the same specs as you are now.

I doubt your RAM needs more than 2.0V unless you run at 1066 or add more modules.