Getting different RAM-amounts showing...

Is your ATI HD 4890 Vapor-X card using your memory? It might be set to use its own Ram and your system Ram. that would explain the drop from 6 to 4.6.

As for the drop to 2-4g Ram, I would say that either the Ram is not in the correct slots if it is a pair it needs to be in the correct slots. or tricannel would need to be in the correct three slots. Just first things to check I guess.

I am assuming you are using 64x as 32x would not show more than 3-3.25 Ram available.

Thx for input !

My Win 7 is 64x.
I have ckecked the slots and they are the right ones.
The drop in Available Physical Memory is not important,
it should drop when the system is in use. It is the difference between
Installed and Total that is my problem. Btw, Installed always shows 6 GB
so my system recognizes the RAM.

BTW, Welcome to the forum.... I do know that RAM can be partially bad as in a section of the Ram cant be used. Maybe install only one stick at a time and do Memtest on each single stick. I know that when they are in Dual or Tri channel, the writing to the Ram is treated as one stick so it might not be catching the bad sections. I don't know if that will give you a failed test or not though.

I don't know what else to suggest as the Installed Ram amount is correct. I would say the BIOS would also say 6G. You might also want to check in the Event logs and see if anything is giving you an error.

You have a Xeon CPU in a Socket LGA 1366 board? The max memory does nothing - its for debugging purposes. I would reset the CMOS, and then put in a matched triple channel kit if its a LGA 1366 or dual channel system. You should also match the RAM in kits, with the same brand, same timings, same frequency.

Frostmourne said:

You have a Xeon CPU in a Socket LGA 1366 board? The max memory does nothing - its for debugging purposes. I would reset the CMOS, and then put in a matched triple channel kit if its a LGA 1366 or dual channel system. You should also match the RAM in kits, with the same brand, same timings, same frequency.

The socket LGA1366 is right one yes. On the Intel site and on the
manufactor-box that what it says.
And my RAM is a matched Mushkin kit from the same box.
All settings the same of course.
And I have reset the CMOS...

This is very frustrating...
I have rerun the memtest - Memtest86.
It says all is ok - Passed.
I have taken one and one strip out of the mobo, I have
tried all the different slots and I have tried different settings in the BIOS....
Still: Most boots I get 6 GB showing and then suddenly 4...
AArghhh

http://www.gigabyte.us/FileList/Memo...a-ex58-ud5.pdf

Could this be the problem?

According to Intel spec definition that XMP DIMMs and DDR3-1600 above are supported for one DIMM per channel only
(Nore2)
When enabling Dual Channel mode with 2 memory modules, be sure to install them in the DDR3_1 and DDR3_3 sockets
(Note3)
When enabling 3 Channel mode with 3 memory modules, be sure to install them in the DDR3_1, DDR3_3 and DDR3_5 sockets

When enabling 3 Channel mode with 4 memory modules, be sure to install them in the DDR3_1, DDR3_2, DDR3_3 and DDR3_5 sockets


Also, I did not see Mushkin on this list of supported Memory types.

It also says:

Memory modules listed below are for reference only. Due to massive memory models on the market, we can only verify some of them

I have not heard of Mushkin having any known issues with Gigabyte-boards
or vice-versa. (And the modules are installed in slots 1,3 and 5.)
But... - Maybe u have a point. Matching RAM and boards seems sometimes to create
different kinds of problems.
It seems that I just have to bite the bullet and buy new RAM

Does the Mushkin package you purchased allow the RAM to be set up in Dual Channel as the setup had shown: (the performance increase from Dual to TRI is not tremendous)

When enabling Dual Channel mode with 2 memory modules, be sure to install them in the DDR3_1 and DDR3_3 sockets

Maybe try this and see if the RAM still disappears.

Also, CPU-Z CPUID is a great program for seeing what your system specs are for your CPU and RAM and it might shed some light on the problem