The Supermicro C7Z370-CG-IW Motherboard Review: SM's First Mini-ITX Gaming Board

Final Words

Many SFF builds attempt to pack as much performance in to a small box as they can, while others just want an HTPC to put something up on the screen. We haven't tested the other Mini-ITX boards yet on the Z370 platform, but we know from previous experience that a Mini-ITX board can be built to offer a good base of performance and design, each separated only by their features, controllers used, and style. Truth be told, there is nothing that sticks out as a shining star here on this board, however, that isn't really a bad thing. The SuperO C7Z370-CG-IW does have nearly all the features we are to expect out of this platform, even in its tiny size. The board has dual M.2 slots for PCIe drives, four SATA ports for mass storage, supports USB 3.1 on the back panel, uses the latest Realtek ALC1220 codecs, and supports all existing Coffee Lake CPUs, including the flagship i7-8700K. In the end, the C7Z370-CG-IW is a motherboard and has the base tools needed to play games in a small form factor. 

Most gaming motherboards these days has some sort of RGB LED implementation on them and the SuperO board we have is no different. In this case, a strip of RGB LEDs are on the back side of the board under the SATA ports and 24-pin ATX connector. They are able to be customized in groups through the SuperO Booster application and has a few different lighting effects as well as the ability to completely disable if that isn't preferred. 

In the future, we would like to see some adjustments made to the board. First, the power limit is set to 65W which is too low. In our testing, during AVX loads (Blender, POVRay, OCCT, Prime95) we saw power limit throttling which crippled performance in those benchmarks. Raising this limit to 95W (the TDP of the i7-8700K), resolved the issue and performance is right where it should be. Another sore point was the overclocking, which was quite a let down here. The Automatic overclocking raised the voltage too high and neither profile showed better performance over stock and was worse due to current limits being hit. The same goes for manual overclocking. On other boards, 5 GHz wasn't an issue, but here we managed to reach 4.4 GHz before the current limit gets in the way. Now, this is technically Intel specification, but the concern on this board is there are no current limit options in the BIOS to bypass these limits. We reached out to Supermicro when we ran into these issues. They are looking into adding options in a new BIOS release which should add that option in future releases. 

At default, our performance testing lands the C7Z370-CG-IW was right in line with the other boards we have tested so far though in some tests (Blender, POV-Ray), we experienced power limit throttling causing the scores to be well below the average. Once that option was set higher (to 95W), all power limit throttling was gone and all results were in line with the other datasets. It did manage to use a bit less power in idle states, otherwise, it was right there with the others. 

Overall, the SuperO C7Z370-CG-IW is a capable board, if peak performance is not much of a concern. At a price of $191, the SuperO board is at the higher end of the range compared to the competition - given that in the past we have seen ASRock and ASUS mini-ITX boards match the bigger ones with performance and overclocking, it does not bode well for the Supermicro brand here. Most users looking at building a performance-focused small form factor system are likely to approach the top tier vendors. The strengths of the Supermicro board are when the user is not overclocking, however cheaper chipsets are available.

Update 5/2:

We have had word from Supermicro - the 65W limit seems to be a run over from the Beta BIOS the board was shipped with (1.0c, the latest online is 1.0, from 10th November). A new BIOS, version 1.1, will be available online in a couple of days to fix this issue. We have asked if this new 1.1 BIOS will have the appropriate microcode mitigations for Smeltdown.

Update 5/18:

The latest BIOS (R1.1), has been confirmed to have the proper 95W power limit at default settings. This change prevents premature throttling during heavy loads at stock settings. We have also confirmed this BIOS does include the appropriate microcode mitigations for Smeltdown. 

Other AnandTech Z370 Motherboard Reviews:

• The Anandtech Coffee Lake Review: Initial Numbers on the Core i7-8700K and Core i5-8400
• Analyzing Z370 for Intel's 8th Generation Coffee Lake: A Quick Look at 50+ Motherboards
   
• ($250) The NZXT N7 Z370 Review [LINK]
• ($191) The SuperO C7Z370-CG-IW Review [this review]
• ($150) The GIGABYTE Z370 Ultra Gaming Review [planned]
• ($144) The GIGABYTE Z370 Gaming WiFi Review [planned]
• ($397) The ASUS ROG Maximus X Apex Review [planned]
• ($180) The ASUS Z370-I Gaming [planned]