probably timing too tight, low volt, or ram too hot/no active cooling..
well, my dt-d43 able to do 3-4-4-10 memtest stable n 2.5-4-4-10 sPi 32M stable at 265 1T 2.8v
probably juz my luck

well, cant say much there..
my ram was able to do 2.5-3-3-10 till 250
how bout u try a few loop of memtest test 5 with
3-3-3-x
3-4-3-x
2.5-4-4-x
3-4-4-x

but its best to go with the loosest 1st [3-4-4-x] juz to know how high ur ram can go
saves time too
timing tightening comes later

huh dude..mind to tell us ur result..

burn in with the most minimal error... try see after a few hours whether the errors are gone