Why are tighter timings more stable than the looser in my case?

[Ricemarine]

Ok, so pretty much, apparently my current settings for test are.

Frequency: 272 mhz (X10 multiplier = 2720 mhz, VCORE = 1.62v (1.45X110%)
2.5-4-3-7 1T
TRC = 7
TRFC = 24
TRWT=2
TRRD=2
Vdimm = 2.75v
Corsair TWINX1024-4400C25

Now, if I try and loosen the timings to oh so...

2.5-4-3-8 1T
TRC = 7 or 8
TRFC = 24
TRWT = 2 or 3
TRRD = 2 or 3

It would be unstable...
I didn't expect such tight timings to be stable?...
What's the deal?

 

[karioskasra]

Running out of spec works both ways on some RAM. When I pushed my ocz plats up to 4-4-4-8 or even 3-4-4-8, it wouldn't even boot and I had to clear the cmos (It's rated at 2-3-2-8).

As for TRRD, it's temperamental in some cases, because there's one setting between 00 and 04 that it'll perform well at, and anything lower/higher will cause instability.