Upgraded memory issues

[highlandbobby]

I am currently running an Intel i5-750 processor on an Asus P7H57D-EVO mobo with a 4GB Corsair CMV4GX3M2A1333C9 kit (built August 2010). I purchased another identical 4Gb kit recently to bring my total memory installed to 8Gb and that's where my problems started. The total memory is recognised by the operating system (Win 7 64) but after a short time of running, the system crashes posting a dialog box saying that there is a hardware problem, though it doesn't define what kind of hardware problem. I have had the sticks in and out and swapped around but the problem doesn't go away. If I run the chips in 4Gb mode dual channel in slots A1, B1 (as required by the mobo - will not operate in A2, B2 slots) then everything is sweetness and light. As soon as a I populate all four slots, the fun begins. I have run Memtest86 on all the sticks placed in slots A1, B1 in various combinations to check all four. No problems are noted and the machine runs fine. However, when Memtest86 is run with all four slots occupied, I get hundreds of errors.

 

The sticks are properly recognised in the BIOS; the voltage and latency are reported correctly; the model numbers of all four sticks are identical. This appears to me to be a mobo or cpu issue (the memory controller is on the cpu, not the mobo). I understand some Asus boards can be very picky when it comes to memory, but these memory kits are supposed to be compatible. Some guidance would be appreciated.

[Synthohol]

I but these memory kits are supposed to be compatible. Some guidance would be appreciated.

they are not supposed to be compatible with 2 kits, only one.

see the mixing ram links below.

[highlandbobby]

they are not supposed to be compatible with 2 kits, only one.

see the mixing ram links below.

 

Hi - thanks for the response. I am aware of the dangers of mixing and matching RAM, which is why I chose matching Corsair kits! I've built several systems before and never had a problem when upgrading the memory despite mixing manufacturers. However, I did know Asus boards could be a little picky, but it is unreasonable not to be able to upgrade later by adding additional memory - you should certainly not be expected to change the whole lot :(: Memtest86 and CPU-Z show all the sticks I have as being identical (all VS2GB1333D4). So, would you suggest getting a 4 stick kit if available, or go for a 2x4Gb modules. Which kit would you suggest? Thanks.

[Synthohol]

when the memory controllers started residing on the cpu instead of the board the mix-n-match ram thing went into the toilet.

the odds are pretty low that you can get 2 kits to play nice together, its not impossible but because of the random unforeseen compatibility issues Corsair and other ram makers only suggest support and guarantee one package of ram per board.

 

i would get the lowest number of sticks for the highest capacity like a 2x4 kit instead of populating all 4 slots.

[highlandbobby]

when the memory controllers started residing on the cpu instead of the board the mix-n-match ram thing went into the toilet.

the odds are pretty low that you can get 2 kits to play nice together, its not impossible but because of the random unforeseen compatibility issues Corsair and other ram makers only suggest support and guarantee one package of ram per board.

 

i would get the lowest number of sticks for the highest capacity like a 2x4 kit instead of populating all 4 slots.

 

Well, I'll give it a shot. I have heard that the on-chip controllers struggle when all four slots are filled. And this is progress? Anybody want to to buy 2# 4GB DDR3 1333Mhz kits? Lol. Thanks.