Asus Z170-A w/ Corsair Vengeance LPX DDR4 3200mhz... XMP Not working

[overclucker]

Hello,

Just built a new system with memory that is suppose to be rated at 3200mhz.

When i run it with defaults the memory runs closer to 2100-2200mhz. If i turned on the XMP switch or turn on in the BIOS i get an overclock fail.

If i change the DRAM freq in the BIOS to 3200 it will pass memtest86 for 9 hours. But seems to get hung up when restarting the PC after booting to windows, coming back to an Overclock failed screen.

How do i get the advertised speeds from my memory?

Specs:

Asus Z170-A
i5 6600k at stock clocks
Corsair Vengeance LPX DDR4 (CMK16GX4M4B3200C16R)

 

[Woomack]

Point is that most higher clocked memory kits are not working at XMP settings on Skylake. There are small differences that make them work.
Probably your memory was designed for X99 platform, not Z170 ... actually there is info on Corsair's site that they designed this memory for X99.
From 3000+ kits I was able to run only G.Skill Ripjaws V at XMP so far. Even older G.Skills couldn't run. Also it's easier to set kits with Hynix IC manually at higher clock ( like main timings from XMP and everything else at auto ) than Samsung which is in most memory kits right now.

 

[overclucker]

Point is that most higher clocked memory kits are not working at XMP settings on Skylake. There are small differences that make them work.
Probably your memory was designed for X99 platform, not Z170 ... actually there is info on Corsair's site that they designed this memory for X99.
From 3000+ kits I was able to run only G.Skill Ripjaws V at XMP so far. Even older G.Skills couldn't run. Also it's easier to set kits with Hynix IC manually at higher clock ( like main timings from XMP and everything else at auto ) than Samsung which is in most memory kits right now.

Ah, just went to their site and i see that as well (http://www.corsair.com/en-us/vengea...66mhz-c15-memory-kit-black-cmk16gx4m4a2666c15) I also see the i5 supports up to 2133 memory under memory types. (http://ark.intel.com/products/88191/Intel-Core-i5-6600K-Processor-6M-Cache-up-to-3_90-GHz)

Now i have a couple more questions:

1. So i need to manually adjust freq/voltage/timing if i want to get to 3200mhz or higher?

2. Since i have a Z170 chipset, should i return this memory designed for X99?

3. Besides XMP not working, could anything else be limited using memory designed for an X99 chipset on an Z170 chipset?

 

[Woomack]

1. Yes. Usually all you have to do is to set main timings from XMP and/or slightly higher voltage ( ~1.4V ) but all depends from memory kit.

2. All depends what you expect from memory. Better will be 2x8GB kit in your case. If you know how to set it manually then it won't make bigger difference but if you want it to work at XMP then you need memory designed for Skylake.

3. No. It's only matter of XMP profile and/or timing table programmed in memory. In most cases you can set all these timings manually if motherboard have all required timings but it's not always easy.

 

[overclucker]

Would i benefit by selling this 3200mhz memory and buying 2400MHz and just OC it to 3200+? I could save $175 by returning my 3200 memory and buying 2400 and then OC it.

Or is there actual differences between the Corsair Vengenace LPX in the chips besides set at different freqs/timings.

 

[Woomack]

I would return this 3200 kit ( if you can ) or sell it ( if price will be high enough ) and get something like G.Skill Ripjaws V 3000 15-15-15 or 3200 16-16-16. Point is that these kits are on the best IC available right now and they're still in good price. Also I was testing both and are working fine on Z170 boards.
Using 2x8GB you won't set much higher clock than 3200. Usually 3400 is max for most boards. 2x4GB are overclocking better.
New DDR4-2400 kits are on similar memory chips as 3000+ but not all of them will make 3000+ at reasonable timings/voltages. Manufacturers are usually picking best batches for the highest series and are additionally testing them at higher frequency. It's one of reasons why higher clocked memory cost more.
On the other hand you can find the best memory chips even in 2133 kits, matter of luck.

 

[thefly]

Hello,

Just built a new system with memory that is suppose to be rated at 3200mhz.

When i run it with defaults the memory runs closer to 2100-2200mhz. If i turned on the XMP switch or turn on in the BIOS i get an overclock fail.

If i change the DRAM freq in the BIOS to 3200 it will pass memtest86 for 9 hours. But seems to get hung up when restarting the PC after booting to windows, coming back to an Overclock failed screen.

How do i get the advertised speeds from my memory?

Specs:

Asus Z170-A
i5 6600k at stock clocks
Corsair Vengeance LPX DDR4 (CMK16GX4M4B3200C16R)

I had some stability issues too with my new system. For the most part they are sorted with updating the bios to most recent version.
Is your bios updated?