Review: Intel DX79SI and Intel Core i7 3930K - Page 1
Forum section: electronics / general

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 11, 2012, 04:51:03 pm
content: I'm putting together a PC that has an Intel DX79SI/i7 3930K platform. It's not quite finished yet (a lot of custom electronics design and case modding to do) but I do have it working. (Note that I work for Intel, so I got those parts for half price.)Pros:* Excellent performance. Turbo Boost really helps with single threaded applications like Xilinx ISE.* Supports up to 3 card SLI and Crossfire. Excellent for scientific computing applications.* A lot of "expert" settings in BIOS, very unlike typical Intel boards.* Capability to operate without a video card for server use.* Support for up to 4 "smart fans".* 2 SATA 6Gb ports, good for SSDs.* Dual USB 3.0 controllers. Useful when USB 3.0 hardware becomes more common.* Supports 1394, very good for the video editors still using 1394 cameras.* Dual Gigabit.* WiFi/Bluetooth adapter included.* Debug LEDs and buttons for bench testing.* Includes numerous stickers to decorate your case and possibly parts inside it.Cons:* Default smart fan settings are very lazy. Fortunately, they can be set a lot more aggressive in the BIOS.* (Seen in some other reviews) Only 6 SATA ports, but it is a workstation board. I have yet to see a workstation with more than 6 hard drives. Those building a small server with the board can use PCI-E SATA or SAS controller cards.* A little expensive at retail price, but well worth it if you need it. (Like I said, I was lucky to get it for half price.)* RAM slots very close to CPU socket. Large heatsinks make 2 slots unusable, which means only half of the slots are usable since it's a 4 channel design. Even then, 16GB of memory is a lot. Low profile RAM would probably still fit should 16GB be insufficient.* Debug LED display only displays a boring "00" after boot. Would be nice if it displayed something like current CPU temperature.* Latching "BIOS" button on rear panel can cause problems for remote power on or reboot if accidentally pressed. A non latching button would be better.

author: T4P
author_rank: Super Contributor
timestamp: March 11, 2012, 06:17:29 pm
content: Ahh you rich bloke , did you really need all the power ?I have a setup with a Phenom X6 1090T with a Biostar TA890FXE , i can place up to 4 GPU's ( I only used 2 , 6850's )But really , i sold that away for a substantial amount . I now use my laptop and really , a Bulldozer and 2 7850's gets you anywhere .But anyway , you work for intel , it would hard to tell your boss that you are making a AMD purchase LOL !Nevermind my empty wit and humour , there's isn't any anyway .Nice deal to get it half price !And if you do not know , the DX79 has the SAS ports disabled , but one manufacturer left it enabled on purpose , but that would cause all sorts of wreck to happen .Traditionally to comply with the ATX standard RAM slots have no choice but to be very close to the cpu socket .And you are probably right , 8GB is just enough .Low profile ram = lack of speed , sometimes RAM speed is your best friend , just because i say it like this doesn't mean they are all low speed , there are decent ones but if you need fast ones , really , don't look at low profile chips . They have no way of dissipating excess heat brought on by overclocking ,remember what extreme overclockers do ? Watercooling . High performance chips only come in collosal size .But WHATEVER ! We all have our personal preferences , just me harping crap on EEVBlog Forum .

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 11, 2012, 06:51:47 pm
content: There's no such thing as too fast in the PC world. Because I got the motherboard and CPU for half price and used recycled parts where it makes sense, I was able to put together the entire system for less than $1000 and that includes an Atom platform for the low power mode.I'm not sure about low profile RAM being slow since they're most commonly used in blade servers. It's true that it's a lot more expensive than normal RAM, though. But for now, 16GB really is a lot.

author: T4P
author_rank: Super Contributor
timestamp: March 11, 2012, 07:38:06 pm
content: Quote from: NiHaoMike on March 11, 2012, 06:51:47 pmYou didn't really catch what i meant , 16GB is a LOT ! But yeah blade servers do not need extremely fast RAM speeds , they only need fast I/O and collosal amounts of raw power .But yeah , $1000 dollar for this much is really frankly the best thing you can get on earth .But hell , too fast ? No way . Too fast unless you have been using a Pentium III forever (HAHAHAHAHAHAHA!)

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 11, 2012, 08:44:54 pm
content: If I somehow added a fast set of digital inputs (thinking some sort of USB 3.0 board), it would work great as a logic analyzer. And 16GB of good 1.6GHz RAM is surprisingly cheap nowadays - $80 or so.And another reason to get a lot of RAM is to use most of it as a disk cache. Good SSDs are still really expensive so if performance is the only (real) reason to use a SSD, it's probably better to just cache a HDD.

author: SeanB
author_rank: Super Contributor
timestamp: March 11, 2012, 08:50:33 pm
content: I think Samsung released some low profile DDR3 modules recently, specifically to address the problem of low clearance but still having high performance.More memory is always better than having swap space, as you cannot wear out a DRAM module from writing to it. With enough ram you will be unlikely to run out of memory with most normal usage patterns.

author: Rufus
author_rank: Super Contributor
timestamp: March 11, 2012, 08:51:56 pm
content: Quote from: NiHaoMike on March 11, 2012, 06:51:47 pmTrue but I have generally maintained that if it isn't twice as fast as the one you currently have it isn't worth upgrading because you won't really notice the difference.I built my main PC a little over 2 years ago with an i7 920 which happily runs all its cores at 4.2G. I recently got a new notebook with an i7 2670QM. A single thread benchmark on that runs about 20% slower than the 920 with a 33% slower clock so clock for clock the Sandy Bridge stuff doesn't seem to be very much faster (maybe it is in specific areas).Given that 2 extra cores will hardly ever make a difference (in my typical usage) will something built with the latest and greatest (and reliably overclocked) be twice as fast as my 920? Doesn't seem that way, what do you think?I just looked at some PassMark CPU Mark results, the 2670QM scores 6800, extrapolating a 920 at 4.2G would be about 8800, the i7 3930K is 13,500 but about 1/3rd of that is from the extra cores.

author: T4P
author_rank: Super Contributor
timestamp: March 12, 2012, 04:09:59 am
content: Quote from: Rufus on March 11, 2012, 08:51:56 pmBut . 2670QM is a LAPTOP CHIP .

author: T4P
author_rank: Super Contributor
timestamp: March 12, 2012, 04:12:12 am
content: Quote from: NiHaoMike on March 11, 2012, 08:44:54 pmDisk cache disk cache ... 1.6GHz is THE pretty much middleline for DDR3 , i was referring to how you won't find a 1.86GHz ( The only known processor line to be able to use 1.86GHz reliably is Bulldozer/Llano)

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 12, 2012, 04:17:52 am
content: My previous machine is a 1.6GHz Core 2 Duo so it's quite an upgrade for me. Thing is, that old machine (one I bought for college) worked for just about everything that common electronics work calls for, except it would have difficulty running multiple IDEs simultaneously for mixed architecture designs (PIC24, FPGA, and Android for example) and the Xilinx ISE would take a long time to compile. Combine that with an idea for a dual mode PC project and that's why I decided it's time to upgrade.