ASUS Z8NA-D6C Dual LGA 1366 Intel 5500 ATX Dual Intel Xeon 5500 and 5600 Series Server/Workstation Motherboard

Pros: If you want a cheap dual nehalem xeon workstation, this is the way to go. ATX form factor means I can use my old ATX case with no problems. Also the motherboard needs only a single 8-pin CPU core voltage power connector in addition to the regular 24pin connector, which means I can use my PCP&C 750 silencer quad to run a dual cpu machine. I don't have to deal with SSI-xxx, EATX, etc etc thus saving a lot of money. Things seem well placed on the motherboard given an ATX form factor, and the inclusion of the PCIe16x2 slot is a plus. I'm using my old 8800 Ultra on my build. The PCIe16 slot however lacks a retention clip. I didn't have any problems using my 8800 ultra though. Can use regular DDR3 memory. Server memory not required.

Cons: As another reviewer had mentioned, spacing is tight. I'm using the Dynatron T667 heatsink+fan to cool the CPUs. There'r no obvious orientations for the coolers. Compromise is necessary, and currently I have hot air blowing over one of my memory DIMMs. No on board audio, but I'm using an old PCI sound card for that. Not really a con but the board doesn't have a PATA port. I wanted to use an old PATA CD drive but couldn't do so.

Overall Review: All in all an excellent board for those seeking more cores for cheap. -Dual Xeon E5520 -Dynatron T667 heasink+fan

Pros: Standard ATX Case, standard ATX power supply, all standard PC class devices - a much less expensive and far more easily implemented XEON 5500 series solution for a one-off than the typical rackmount case & power supply required in the past. Has been rock solid so far as a VMWare ESXi platform.

Cons: As has been mentioned, spacing is very tight. Non-Intel thermal solutions pretty much WILL NOT FIT!

Overall Review: The best CPU cooler for use with this board (by far and away) when used with the 5500 series Xeons seems to be the better of the Intel 5500 series coolers - the STS100C referenced in the Intel support document below. http://www.intel.com/support/processors/xeon5k/sb/CS-030328.htm It fit's beautifully on the board (even with 2 CPU's) is near silent and runs quite cool even under load.

Pros: Solid.

Cons: BIOS may be outdated. * read other thoughts on a fix *

Overall Review: You can call Asus in the USA at 812-282-2787 op 1 op 3. Give them your serial # and they'll tell you your manufactured date. If your board was manufactured before March 2010, you will have an outdated BIOS. IF that is the case, they will sell you an updated BIOS chip for $5 + $15 ground shipping (from IN) or $25 overnight shipping. You just pop off the old chip and put on the new one, then boot up with a 5600 series CPU. Newegg may credit you up to $25 for your trouble, since the headline of this motherboard says 5600 CPU support.

Pros: cheap, decent documentation

Cons: If you're unlucky enough to get an older version of the BIOS, you won't be able to use the westmere six core cpu's (X5650 in my case). I don't have a spare 5500 cpu to flash the BIOS. I called Asus, and they were supposed to overnight a new BIOS to me (at $25 shipping), but sent it ground instead, causing further delay.

Overall Review: Shame on Newegg for advertising that this MB supports 5600 Xeons...you can look through this thread and see many examples of the same issue.

Pros: This motherboard works seamlessly once you get it setup and running good. - Great price for Dual socket

Cons: This is why I gave it -2 eggs. The first motherboard I got from newegg was not registering 2 of the dimms. It was suppose to read 12 gigs of ram and it only read 8. Moving them around did not change anything. So I RMA it and get a new one from newegg. I thought I was home free. I guess not.I get the new motherboard install it and load the OS. Boot up in BIOS ect everything seems fine. Until I moved the server to the basement and all of the sudden I noticed the BIOS reset. So I thought oh well the CMOS batter must be not in place or what ever. It was just fine. I then found out that the BIOS was resetting upon every power cord unplug. I changed the CMOS battery. Checked jumpers, updated bios. I won't name them all. But I called ASUS and told them my frustrations. They said sounds like you have a defective motherboard. I was not happy 2 in a row. So insted of RMAing to Newegg. I RMA to ASUS, they overnight shipped me one and got it the next day. All is working well now.

Overall Review: Other thoughts to my cons was if you like the board get it. I sure hope you don't have as bad of a time I did. But it sure is a nice board for a great price. When it's up and running it's seamless too. One other con is this board is very cluttered. If you browse through other reviews on this mobo you will see people have problems fitting their CPU coolers next to each other. I used Item #: N82E16835203002 had NO issues what so ever it's a snug fit. Also the CPU cooler item I listed is a very very good cooler. Made by intel the fan's on the thing run at 8300 max speed. It will keep any CPU nice and cool. Those CPU coolers also will fit in a 2u server.

Pros: ATX form factor is a huge plus. Dual LGA 1366 slots are located almost exactly horizontal allowing my heatsink on the second cpu to create a airflow, which creates less air resistance for the air going over the first cpu. Came with an ASUS MIO audio card as a combo deal. Dual NIC is nice feature so I don't have to waste pci slots. Only 1 PCI-E slot, I used it for a GPU. The sata ports are straight up which is a life saver instead of facing towards the front of the case. Triple channel support for DDR3. Single 8-pin CPU connector needed not two.

Cons: Not much room between the heatsinks and the ram slots. I had to modify the edges of my heatsinks to fit. All I did was round the edges of my retention clip for my consumer based heatsinks. I wish the raid was hardware based and didn't require drivers. I guess they won't move beyond a hard drive controller with extra features. Only two usb slots in the rear. I would rather have 4 usb slots in stead of having the two p/s 2 slots. No retention clip for the pci-e, not that I need it, but it seems pretty standard on consumer boards.

Overall Review: Running 2(two) Xeon 5530's with turbo they usually run at 2.8ghz over the standard 2.4ghz. Having 16 cores (8 physical x 8 logical) makes visualization much faster and responsive. I use this as a workstation for video editing and my encoding times are around 60% faster then my single O.C. quad-core. A single quad was fast, but I couldn't do anything while encoding. At least with 2 cpu's I can continue to work on other projects as the pc encodes in the background. Windows 7 has issues in load balancing (and clock interrupt BSODs) compared to Linux. I just run windows 7 in a virtual machine instead now when I need it. I've never seen an onboard usb slot above the sata ports before. I suppose this is for holding drivers at all times?

Pros: i love it, entry level WS board, price/quality ratio wise i think is worth the price. It has all the features i needed and serves me perfectly. Installation was easy, no hassels, no hickups. System: 2xXeonE5520, IntelBXSTS100 coolers, 12GB Patriot DDR31066, HighPoint Rocket Raid2640x4, 4x Fujistu MAX3147RC SAS, Samsung DVDSL223l, CreativeSBX-FIXtremegamer Audio, FSP MOD 700 PSU, MSI , ATI Raedon HD4670, 2x Hanns-G HH24, and an old noname full tower. OS: Windows Server 2008 R2, boot up time is about 30 sec ( mostly b/c of the spin up time required by the drives)

Cons: none for me, am really really happy with the quality.

Overall Review: System is running 8 VMs, and is used for database testing, db application design, interface design

Pros: N/A

Cons: N/A

Overall Review: Just wanted to add something to my previous review. Two Xigmatek S1283V Dark Knight coolers fit on this motherboard. I was using Dynatron T667s, but had to ditch them since the CPUs were running way too hot. With the Dark Knights the CPUs are cool and quiet and I'm am able to use the machine as a workstation.