Question About Ram Timings & Voltage Mismatch

For my new build I have a Core i5-6500 CPU, stated to only accept DDR4, or DDR3L at 1.35V. Now, in the BIOS, it tells me the RAM is running at 1.5V like normal DDR3, despite being 1.35V DDR3L. Does this mean my mobo is overclocking my RAM by default!? I've changed the voltage to 1.350V to prevent damage to the CPU or RAM, but I wonder why it was running higher than it should be to begin with.

As for the timings, the BIOS tells me the RAM is set to run at 1333MHz, despite being sold as 1600. 1333 was the speed of my DDR2 from 10 years ago lol, so do I have to set it manually just like the voltage? All the 'auto defaults' in the BIOS seem to be wrong. It's automatically overclocking the voltage, then underclocking the speed! What gives LOL?

On the same page I have 2 XMP 1.3 profiles. Both are "1600MHz / 8 8 8 24" but with diff voltages. Apparently these are over clocking profiles, but how is 1600MHz an overclock when the RAM is 1600MHz to begin with? The only thing that matches up is the CAS latency of 9. Can anybody help demistify this weirdness?

My specs:-
Mobo: Asrock Fatality z170 k4/D3
CPU: i5-6500 (non K)
RAM: 2x Crucial Ballistix Tactical 4gb DDR3L - PC3 - 1600 (low profile) [dual channel mode]

Cheers all!

 

The UEFI BIOS will do what it's programmed to do by default. My Sabertooth underclocked my RAM as well, and I had to make all the adjustments manually to bring it up to where I wanted it. A lower voltage places a limit on how high a frequency you can push. Also, higher frequency normally means higher latency. The real trick is to find the best balance between frequency and latency for the most efficient data throughput for your board.

Just because you can max out the frequency at a higher latency does not mean it has a throughput which is superior.

BTW, if you don't have liquid cooling, try and take it easy on your CPU.

 

Thanks for the info, I've left the RAM at 1333MHz for now but I'm glad I looked into the O/C pages of the BIOS because by default my board was pushing the RAM to voltages my CPU can't handle (!). I'll do some reading about finding the best configs for what I've got, but what I really don't understand is why the 2 XMP overclock profiles run at stock frequency and no higher.

If I have RAM that was advertised, marketed & stated on the box/DIMM to be 1600MHz, would it be a no brainer to manually set it to 1600 rather than the 'detected' 1333, or would that be risky. I know O/C is a risk, but this is allegedly 1600 RAM so I'm not sure if I'm O/C'ing or not (if I believe my BIOS, then 1600 is an overclock, but if I believe my RAMs specs, its just 'stock speed').

I'm savvy with O/C'ing so I'll definitely leave my CPU at stock speed, its way fast enough for me as it is (I used to have a Core 2 Duo LOL)! GFX O/Cing is as far as I've taken it so far.

 

Set the BIOS/UEFI to use XMP for the memory then change the settings to the stock (introduced with IvyBridge) 1600Mhz and 8 8 8 24 and 1T at 1.35v. Without using XMP, you'll be unlikely to have dual channel set.

 

Thanks! I'll give that a shot soon as I can. So as long as I'm no higher than 1.35v and 1600MHz (the freq. stated on the DIMM & its packaging) I should be good to go? No real risk?

BTW I meant to say I'm "not" savvy with O/Cing LOL. I stick to GFX overclocking because apps like GPU-Tweak make it really easy to understand.

 

Risk, no, they're pretty much standard settings for Ivy and later (DDR3(L) is usually good for 1.65v, my 2x4 Samsung 1600's used the same settings @1.25v, they were just as easy to run at @2000/1.5v and looser timings).

 

Thanks again. I selected the 1st XMP profile (1600MHz / 8-8-8-24 / 1.35V) but I couldn't find an option for the 1T/2T thing. In CPU-Z my RAM shows as "2T" but when I last checked, I'm pretty sure it was 1T. I take it switching to stock speed made the RAM 2T (so now my RAM takes twice as many clocks to operate? eg, a bad thing!).

In CPU-Z the channel# shows as 'dual' but the "DC Mode" (dual channel mode?) field below that is just blank. Is that normal?

Is there any way to use the stock 1600MHz freqs while still keeping the 1T?

 

Yes, once you select XMP, dual channel should be activated. Channels # = Dual is all I see in that segment of CPU-Z too, that's fine, it means that the RAM is in dual channel mode.

If you dig deeper into the Advanced/Overclock settings in the UEFI/BIOS, you should be able to change to 1T, not that it makes much difference, certainly not as much as the terminology reads

 

Confirmed: CPU-Z timings table shows both XMP profiles can only run at 2T... BTW I found the Command Rate options but in the BIOS its listed as neither 1T or 2T, but 1N (auto). Not sure what that means or how I should proceed.

Something else I noticed (maybe not 100% related):-
In CPU-Z I found that the i5-6500 is always running at the max frequency (3.6GHz at a multiplier of x36. That's the "turbo boost peak speed"). With Turbo Boost disabled in BIOS the CPU runs constantly at 3.2GHz x32 (the max non-boost speed). So basically the chip is always running at the highest possible frequency (with respect to turbo boost).

I've read that XMP can cause the Mobo to always "max out" the CPU even while idle, therefore shortening the CPUs life for no reason, BUT, for me this happens whether XMP is on or off.

Cheers!

 

XMP is memory only.

Change the auto to 1T.

Do you have Speedstep enabled in the BIOS?

 

Thanks, I tried to change the CR from 1N to 1T (theres no options, you have to type a value) but it wouldn't let me change it to anything. I type "1T" where it says "Auto" then press enter, but it goes straight back to "auto" no matter what I type (auto setting is 1N). Any other settings in the "primary timing" section CAN be changed (eg. CAS Latency or RAS active time) but CR always resets to auto. I retried with XMP set to none but it still resets. I checked the manual but all it says about CR is 'what it does'. Yea Speedstep is enabled too BTW.

Sometimes the BIOS just locks up & needs a hard reset. This has happened twice now since a couple of days ago. Other times it freezes but wakes back up after about 2 mins. Any ideas what might be causing that? EG, last time I opened the XMP selection list, it froze for about 2 mins. I was about to hard reset, then it came back.

 

Don't fret if you can't change that setting, as I said earlier, it makes little difference. The big one is to set XMP with the RAM makers settings so that you get Dual Channels enabled.

Check for a BIOS update, if there isn't one available, reset the BIOS to defaults and set it all up again.