Which ram config to choose
Which ram config to choose
Consider your setup carefully. Using both 16GB modules at 3200MHz and 4000MHz could cause compatibility issues. Stick with the 4000MHz sticks for consistency, or try to match the 3200MHz clock speed exactly if you want a unified system. For a total of 32GB, Kingston FURY Beast and Patriot Viper Elite II support that configuration.
If you combine them they'll run at the slowest common speed by default. The motherboard should allow you to use the XMP profile of the slower stick. There's a slight chance it won't boot or overclock though. Do you have one stick of each, or are these pairs? If it's one stick each, combining them would also have the benefit of giving you dual channel. If it is four sticks in total, the chance of it not working is a bit higher.
Both models run smoothly at 3200mhz, though I’m curious how CL20/CL16 might influence things. Memtest didn’t catch anything, it kept mentioning a memory lock—probably best to run it as a boot drive for a proper check. As for performance, the two seem pretty similar, so unless you really need one over the other, you might not want to keep both.
3200 CL16 offers a latency of 10 nanoseconds. The 4000 CL20 matches this at 10 ns as well (Latency = CL x 2000 / Speed). In practice, the sticks perform similarly in terms of response time. Speeds of 4000 MT/s are clearly quicker than 3200, but noticeable differences usually only appear in tests. Performance gains slow down once you exceed certain thresholds. The trade-off becomes more apparent with higher CPU speeds like Zen 3, where you may need to boost the I/O frequency to maintain stable performance above ~3700 MT/s.
Cas latency doesn't really impact performance, so 4000c20 is likely to dominate by a big margin. This assumes the secondaries and tertiaries aren't bad, which they probably aren't since 4000 and higher are seen as premium bundles. Viper Elite II appears to be an older model with looser timing, suggesting its ICS might differ from the newer ones. Check the burner first to confirm the ICS compatibility—most should work, but a few might clash completely.
It varies based on the workload. The timing details matter too. That's concerning, I purchased a Micron Rev.E 3200MHz CL16 2x8 kit and boosted it to 4200MHz CL16 at 1.5V... It might reach even higher speeds with increased voltage.
Eh i personally didnt see anything from cas 7 -> 5 on ddr2 1000, spi and wprime were mostly within error but ill give it the benifit of the doubt and say c5 performed ~0.05s better than c7, wonder if there are any other memory benchmarks. ill check on ddr3 once i get a capable board and i will be getting a couple z77 and a z68 soon, hopefully shouldnt be too far away from ddr4 behaviour wise aside from the obviously lower bandwidth Besides cl gobbles voltage like theres no tomorrow at a certain point so i would advise against overtightening it and instead just cranking the freq, buildzoid did make a vid awhile ago comparing super tight ddr5 primaries and loose ddr5 primaries but higher freq forgot the damn title and the higher freq got the same latency, though tbf primaries on ddr5 are apparently just irrelevant to performance Actually ive only found viper elite 4000c20 reviews to be around early 2021 for the oldest ones so id just assume a release date of this particular bin to be around early 2021 so only ic possibilities i see are rev e and djr Djr is pretty common, rev e seems to be less common aside from ballistix and bare pcb crucials Apparently rev e caps around 1.6-1.65v if you dont run ~700mv vttddr atleast thats what ive read. But even then its kinda pointless running desync fclk or gear 2 unless you can get em fast enough to overcome the latency penalty, rev e should just barely overcome fclk penalty since they usually cap around 4800-5000mhz before timings go to shit. Oh and theyre temp sensitive so make sure to run a fan if you are gonna run high volt
Keep your PC on for a few days while hwinfo runs, then review RAM usage afterward. Ensure you never exceeded 16GB unless you’re using the 4000. What are your 4000 timing specs? If you have a BIOS kit, it’s definitely worth optimizing.