Windows Crashes after taking 6gig of the 12gig out

[roachyuk]

gigabyte x58 ud5...corsair xms3 memory 1600 ...had 12 gig in 6x2gigs...would only ever run at 1066 the memory stable ...just taken 6 gig out and keeping 6gig in..running at the same speed as its meant to run 1600...the pc just keeps crashing randomly with either set of 6 gig triple channel in...he is running at the same speeds as i am as we both have the same parts...mine runs fine....now if he puts the 6gig from 1600 back down to 1333 which is below what it should run at the computer works fine.
Has anyone got any ideas why this happens or came across this thanks.

 

[Orcvader]

So it works with 6x2 but not 3x2? Run a memtest with one RAM stick at a time? Ensure the RAM correct voltages have been set?

 

[roachyuk]

ok sorry need to explain a bit more...yes the 12 gig runs fine at 1066....even though the memory is rated at 1600...so taken 6gig out to use else where so thought would be able to run now at the correct speed being 1600 ....the 12 gig would never run at 1600 anyway think it was because all 6 slots where occupied that stopped it running full speed.
as i said he has the same board and memory as i do and i have no problems....is it possible because he formatted his pc while using the 12 gig....going down to 6 gig gives windows incorrect readings? thanks

 

[bremen1874]

Changing the available memory shouldn’t bother Windows very much. Depending on how Windows is configured you may end up with an inappropriately sized page file, but that wouldn’t cause the problems you’re seeing.

If you have the same boards and memory the quickest way to narrow down the potential causes would be to temporarily exchange memory and see what happens.

 

[roachyuk]

yes weve done that still same problem....weve reset the bios and put same settings in as mine....so probably test the memory in mine next to see what it does....then if its ok move onto something else like the board ....strange though it will only run at a slower speed...