does matrix raid reserve system ram?

[EBrad1]

Just built a low end server using Intel S3420GPLC mainboard, 4Gb ram and Matrix RAID1. Due to customer software limitations, we have had to use Windows 7 32 bit as OS. 2x2Gb ECC ram installed, but 1577Mb is 'hardware reserved'. Is the Matrix Raid reserving this RAM, or something else?

[Daniel_O_Intel]

Hard to say. I would recommend staying with OSes listed on the list at

http://www.intel.com/support/motherboards/server/s3420gp/sb/CS-030739.htm

[EBrad1]

Thanks - but customer really would prefer Windows 7. The reduced memory is not a huge problem, just a niggle as I don't know why it is so. I'm a little like Prof. Julius Sumner Miller - "why is it so?"

[Edward_Z_Intel]

Try to enable the following setting in BIOS: Advanced => PCI Configuration => Maximize Memory below 4GB.

Memory address below 4GB are reserved for BIOS, PCI devices, etc, while 32-bit OS can only access memory below 4GB. See http://www.intel.com/support/motherboards/server/sb/CS-010458.htm http://www.intel.com/support/motherboards/server/sb/CS-010458.htm. This is limitation os 32-bit architecture.

[EBrad1]

Thanks - The BIOS doesn't have that actual setting - only one to do with enabling memory mapped i/o for 64 bit devices to be above 4gb. I've tried enabling and disabling without any effect on the 'hardware reserved' portion.

I know about the 32bit limitation to 4Gb. It is the 'hardware reserved' amount of 1577Mb in Windows 7 that is the problem. I phoned intel tech support, and they agree that the amount that is reserved seems overly large, but have no suggestions. I have no PCI cards plugged in to the mainboard. It is running Matrix raid and stock standard graphics with intel driver.

[Edward_Z_Intel]

It seems that the "Maximize Memory below 4GB" setting was documented but was not actually implemented... The BIOS will reserve certain amount of memory, no matter how many PCI device you're using.

I don't think there will be a quick fix, because as Dan_O mentioned, Windows 7 32-bit is not validated on this board. Do you mind using a 64-bit OS or a server OS that can access more than 4GB memor? See http://msdn.microsoft.com/en-us/library/aa366778(VS.85).aspx http://msdn.microsoft.com/en-us/library/aa366778(VS.85).aspx.

[EBrad1]

thanks - but the customer is running software that prints to some docket printers, and 64 bit drivers are unavailable. 32 bit is the only way for them to go.