Pros: - Supports 6-core E5645
- Supports 48GB of Registered ECC with 4GB sticks
- Two PCIe x16 slots
- Tons of fan headers
- By far the best motherboard manual I've ever seen

Cons: - Chipset fan isn't very quiet but, it's generally only audible when the case is opened. This would be cheap to fix if it bothered you.
- This is a big board but, putting in a large CPU cooler like a Noctua NH-U12DX makes things almost uncomfortably cramped. Those heatsinks will fit but, if the top PCIe slot is filled, it limits your choices on how you can mount one of them.

Other Thoughts: - A number of people have complained that they couldn't get all DIMM slots to work or have had general memory problems. I dropped in 12 Kingston KVR1333D3D4R9S/4G sticks (available on Newegg and verified by Supermicro) and it recognized every stick on the first boot and I've had no problems at all.
- It wasn't clear that the board supported the newer 6-core 5600 CPUs but, it booted up on the first try and detected both chips without issue.
- Fits very nicely in a Lian Li PC-A71F case.

I've built plenty of computers but nothing of this grade and reading the reviews of this and other Supermicro server/workstation boards made me nervous about RAM and CPU compatibility. Sticking with the approved memory list, I've had absolutely no problems at all with this board. Despite the minor Cons listed above, it's an excellent board and I'm very pleased with it.

Pros: Lots of nice features:
Cheap SAS lots of sata ports built in Intel and mega raid, 12 ram slots for a ton of ram, dual PCI-E 16 slots for dual graphics cards

Cons: OK so from day one this board has been a problem. I got it home got it in the case installed my dual Xeon 5520 and the subsequent liquid cooling hardware and as soon as I turn it on boom DOA wont recognize one of the processors. I call tech support ( which is like talking to Peggy from the discover card commercials) and all they could offer me is to RMA the board. So after 2 hours of removing the board (my fault for not testing before installing gran it it is hard to do that with liquid cooling) I send the board back. I got a new one timely and installed it good to go. Recently (and the reason for this review) I just purchased 12 more gigs of ram for a project I am working on (had only 12 before 6 2gig sticks) and wouldn't you know it as soon as I populate all slots the second bank completely quits! It only recognizes 11 of the 12 slots. The top slot on the second bank is bad and I now have to send it in for yet another RMA!

Other Thoughts: I want to love this board. It has all the features I needed for a high end work station but in the 1 year I have had it it has done nothing but constantly have me remove it and send it back which costs me money (as I use it for work and grad school) and time. I would use extreme caution if you are considering this board. I give every company some leeway when it comes to electronics you are buying pieces not a complete system and there is allays bound to be one bad apple every once and a while. But I will soon be on my 3rd board showing me that either I am good at hitting the negative lottery or this board Has allot of issues. And after building sever PC's I am leaning toward the latter.

Build
Dual xeon 5520's Liquid cooled
24 gig of corsair Dominator DDR3 1333 (only 22 work)
Dual Intel X25m SSD raid 0 boot / OS drive
wd caviar Black 1TB Program drive
PNY GTX 460 liquid cooled Graphics card
Antec 1000W PSU
HAF 932 case

Pros: - Rich feature set packed into an affordable product. Running dual Xeon 5506's, 8TB worth of drives, with 48GB of Kingston memory.

- Running comfortably in the 30's (both CPU's) and around 40's with a load.

- I am using this in my home (hehe)

Cons: Strict variances with memory timings. As I have now seen with other reviews it is important to go with memory from their QVL listings. Too bad!

Other Thoughts: I purchased some WINTEC memory initially and I would get to about 65% of OS installation and it would reboot. Emailed SuperMicro asking for advice after trying everything I knew to tweak in the BIOS (replied within 24hrs) and they told me to look at the memory or maybe an issue with the PSU. Opted to purchase memory from their QVL list and I was able to get the OS installed. It was a minor headache.

Bare in mind that the memory issue will not prevent me from a SuperMicro board in the future. I would hope that if someone from SuperMicro is reading these reviews you have at least a few people complaining about the memory compatibilty. Please loosen up the memory restrictions!!

To the user who was having an issue installing Windows 7 I would suggest looking at your memory and go with a brand that is on their QVL listings. I have and now I have W2K8 R2 as a member server with several VM's, including Windows 7.

Pros: This board is excellent in regard to features and options. It runs great with linux and works out of the box no problem. Running dual 5620 westmeres with 24GB of patriot memory and 1200watt power supply.

Cons: I am a long time systems engineer and have been trying to get windows 7 to just install on this. It consistently reboots itself during installation at the same spot (extracting files). I have tried different drives (thinking it might be the SSD) and still consistently happens. I have tried different cables, busses, you name it and same thing every time. This is only with windows 7 (pro, ultimate etc for dual socket support)

Right now out of the box support for windows 7 is terrible and/or non functioning.

I have gone through as many diagnostics as I can in linux and have not found any issues with the hardware or IO. I have run memtests, IO tests to disk, etc and no errors or blips even with syslog debug.

This is clearly a compatibility issue with Windows 7 and this board.

Other Thoughts: This is intended to be my virtualization platform so windows 7 isnt necessarily required. I was hoping to dual boot for some gaming but windows 7 is just problematic during installation

Pros: Lots of features and expandability

Cons: Did not fit in supposedly extended atx case (corsair HAF)
2 usb ports at the back are not working, but I don't think I will dissable my hole computer just for that.
Everytime I email to supermicro support I get no answer. Is this becaus I am in Canada or what?

Other Thoughts: The choice for this kind of board is pretty small. So if you want to have all those features, you have no choice to buy this.

Pros: 8 sas ports which you can set to IT mode and use as additional sata ports for software raid if you don't want to tie yourself to LSI RAID or if you want to span 10 or 12 HD's from the sata and sas together in a software raid.

rock solid for 6 months

Cons: why don't all sever motherboards come with onboard vidieo? baught this in a hurry cause the X8DT3-LN4F-O was out of stock at the time, didn't realize it was two serial ports instead of serial / vga
hot plugging HD's doesn't work with ubuntu 10.04 :(
LSI sas ports face forward and can be a tight fit with the gigantic splitter cables plugged in, make sure you get a roomie case or you'll lose a HD bay / have to break out the dremel.

Other Thoughts: x5620
3x2gb ECC unregistered
ubuntu 10.04 LTS

support was responsive in providing sas IT mode firmware and support, but don't always expect same day replies.

Pros: -Tech support at SuperMicro was responsive and somewhat knowledgeable when I called/e-mailed...more on this below.
-Board layout is great, CPUs idle in the mid-high 30s and hangs around 55° at load.
-I want one at home

Cons: I wish they would have a more complete list of compatible RAM. Because the RAM i purchased wasn't on their list they couldn't help me out beyond the basic support they gave me. The RAM tested good, all sticks were in the proper slots, and it ended up being a DoA board (a new board booted first try). Beyond that I have nothing but good to say about their customer service

Other Thoughts: WINTEC 6GB Model 3SR33590K-13
SeaSonic X750 Gold
Intel Xeon E5520
Kingston 64GB SATA II SSD
FirePro V7800
Noctua NH-U9DX

This computer is just too fast. CAD/CAM works great and our engineers couldn't be happier. For anyone getting this board I seriously suggest the Noctua Heatsink, it is one of the best heatsinks I've ever used.

Pros: Great expandability in term of memory up 192GB using ECC registered. 96GB is assuming you only using 8G ECC registered per slot. Newegg need to update the spec.

Cons: Poor documentation in term of trouble shooting. There's no extra USB connection that you can add at the back. Lucky I was able to use my asus p5b one. They do have two usb connection inside the motherboard rather than the pins.

Other Thoughts: Just a heads up for those using logitech g11 keyboard and USB receiver for the wireless mouse connected to g11 keyboard. You will getting 3 pairs of beeps and you will also see "keyboard not functional" on the bios event log. I'm thinking it is normal since it has no problem loading the OS. And also, if you are using those Ms keyboard+mouse which comes with one USB receive. You will getting 2 pairs of beeps. I alreasy inform Supermicro about this hopefully they will come out a new firmware update or beeps is just normal. I personally want them to address this issue.

Pros: Bought this board from the egg and thought it was bad. Went and RMA'd it. Then it occurred to me that the board probably didn't have the latest bios version to work with the dual X5680 xeons I bought. I got sent a new board but this time I ordered a 5500 series cpu for cheap. It posted and sure enough, the bios was out of date. Flashed it, and this board works great. Paired it with 48 gigs of ram, and lots of storage. Couldn't be happier!

Cons: The fact that supermicro's manual acknowledges the new processors and even goes so far as to talk about them, but then does not flash the bios to support the new chips. Hmm. Could this be a marketing blunder on the part of supermicro?

Other Thoughts: I've been using supermicro boards for my servers and workstations for years. They are definitely in a class of their own when it comes to excellence. Supermicro rules the server/workstation arena.

Pros: Solid, well built and flawless.

Cons: None

Other Thoughts: To the guy who was bashing the board and SM in general I have one question to ask?
Which division of Asus signs your paycheck?
I've been dealing with SM for the last 7 years and all I can say is you called the wrong company.
When I have called them for advice I get adults that "know their stuff"
You mention Asus. I'm very familar with them.
The Z7S-WS dual socket 771 board especially.
Want to burn one out? Just do a reboot and bingo, dead board.
You don't beleive me? Go to the Xtremesystems forum to the WCG section and read for yourself.
At least a dozen dead ones from just a reboot with a E0 stepping cpu.
Asus will do nothing about it except talk, and talk, and talk until you get sick and tired and walk away.