On 11/24/10 4:23 PM, mcclnx mcc wrote: > Thnak you for answer. > > We can NOT use X86_64 due to application NOT support 64 bits. > > If I take some RAM out of server (for example take out 32 GB RAM and left 32 GB RAM on server), will problem fix? 16GB was the maximum recommended for PAE all along. PAE was a crutch to get above the inherent x86 32bit architectural limitation of 4GB. 32GB would likely work, and just use half the kernel address space, instead of most all of it. Have you tested this 32bit application on x86_64 ? you may simply need to install the correct 32bit dependencies. The only absolute unsolvable problem would be if this application included binary custom kernel drivers which aren't available in 64 bit, and if this was the case, I would hammer on the application vendor.