Are there any server grade motherboards that works on all OSs?

[gea]

VT-d is controlled by the Northbridge and is independent of the CPU used.
Only reason for Xeon is if you need/want ECC or dual socket.

only Xeons and i7 (not even all of them) supports vt-d on some, mostly server-class mainboards. even on chipsets thay may be able to support, you can have problems due to bios not supporting it properly.

so if you really need vt-d for ex to pass-through a storage adapter to a virtualized os, like me with my napp-it all-in-one solution (esxi-virtual server + virtualized ZFS NAS/ SAN + virtualized network switch in a box) you should really buy a 3420 or 5520 mainboard and a Xeon.

see
http://ark.intel.com/VTList.aspx
http://wiki.xensource.com/xenwiki/VTdHowTo

 

[zicoz]

The more I think of it the more uncertain I get. Now I'm even looking at the X8ST3-F and x8ste , but I'm worried about it pulling alot of juice without really giving much back in terms of performance. Do you think there are any chances we'll see some 4xPCI-E slot boards for some of the lower wattage platforms in the next couple of months?

 

[nitrobass24]

If you have the BIOS and your Hypervisor configured properly for P-States and C-States then when it is sitting idle it should not consume much power.
The link below is specifically related to ESX, but he explains how the different power states work. They power states function the same even within Windows/linux too.
http://jasonnash.wordpress.com/2010/11/24/a-look-at-vspheres-power-management/

 

[zicoz]

Ok, thanks, what if I buy a motherboard with 2 CPU slots, like the X8DTH-6F will have have to have to CPUs?

 

[john4200]

No, you can use only one CPU slot, but then you can only use the RAM slots for that CPU.

 

[layerbreak]

Thats sounds interesting.

Whats with the onboard slots? Are they shared to every CPU?

 

[john4200]

The CPU(s) has a 3-channel DDR3 memory controller on it. The dual-1366 motherboards are set up so that the memory controller from each CPU controls half of the RAM slots on the motherboard.

Typically, this is not a problem for single-CPU operation, since the most common configuration for these motherboards is 12 total RAM slots, so 6 per CPU, and most people who only want 1 CPU don't need more than 6 RAM slots.

If you do need more, there are motherboards with 18 RAM slots, which is 9 per CPU.

 

[zicoz]

Looking at the motherboard overview it seems that one CPU is connected to 4 of the PCI-E slots and the other to 3 PCI-E slots. Does this mean that 3 of the PCI-E slots are disabled if one only uses 1 CPU?

 

[nitrobass24]

On the Intel 5500 and 5520 chipset mobos that is no longer a problem. With one CPU you can still use all of the memory slots and all of the expansion slots work.