I5 RAM problems

[CoolZone]

It seems I have a little technical issue. I have an ASRock P55 Extreme and with 2 I7 memory kits ( 2 modules from 3 ), at BCLK 200MHz, the system is fully stable there is no problem, no errors at all, but with 2 I5 memory kits I have tested so far ( Mushkin and Patriot ), one 1600MHz and one 2000MHz, I see in BIOS, in Vista x64 System Properties 4GB RAM installed and in Task manager only 2GB usable.

What could be the problem?

[Leeghoofd]

Your Vista and co eats up 2Gb out of the 4Gb

[SoulsCollective]

So, sorry, if I understand correctly, you've bought two i7 kits (3*2GB DIMMs), and are using two out of each kit for 2*2GB+2*2GB=8GB? And this works fine? And both i5 kits you've bought (2*2GB), using all sticks out of each kit for 2*2GB+2*2GB, show 4GB installed, 2GB usable?

If so, check your mobo for warping and your CPU mount. I often have this issue with my eVGA Classified - Taskman and Windows will tell me only half or so of my RAM is usable - and it seems to be to do with the contact traces between the CPU and the RAM slots being distorted by PCB warping (I'm using an EK Supreme without backplate, which puts a fair bit of pressure on the board around the socket area due to the mounting mechanism design).

[Ket]

Might be a BIOS compatibility problem. Check to see if you have any options in your BIOS along the lines of memory remapping.

[CoolZone]

I have fixed it. It was a BIOS issue. Thanks guys!

[doom_st]

memory remap,right?