Differences between 3200C14 and 3600C17 as well as CPU compatibility

[whm1974]

Xeons CPUs that support over 44 lanes are more expensive need much more expensive ECC RAM, I guess.

Yes but if he doing something that is really important, then he does need to use ECC memory.

 

[BonzaiDuck]

The reason for ECC memory, usually, is to support critical computer applications, such as monitoring a hundred hospital patients and vital signs, running a nuclear power plant or supporting an air-traffic control activity -- that sort of thing. I think ECC is both more expensive and comparatively lagging in speed, because of the hash code calculation of the extra bits of memory. Other types of work, in which the system owners repeat any number complex simulations, or even gaming hedge funds and margin calls, would not suffer much from an occasional alpha particle tripping a bit.

I have a set of 4x4GB=16GB Corsair XMS 1600 DDR3 RAM @ 9,9,9,24. It came used in a motherboard and processor bundle, and the original owner had used his Sabertooth Z77 rig to do Folding@Home or SETI for hours daily. He didn't overclock it, and the 3570K i5 processor when proceeding through its daily toil, would reach 55C degrees. It was never abused, but was certainly used. You could still run HCIMemtest64 on them with 1,000% coverage -- the grueling all-nighter-into the next day test. There are patterns to failures over a product's life-time; there are things called "infant mortality," which -- if not failing in the first 72 hours, are more and more likely to last what seems forever.

I also remember an AnandTech interloper I encountered at the "Cases and Cooling" forum. He had a couple fans that might have been 18" to 24:" in diameter, with a roomy cubicle case. The man had a dual-processor Xeon motherboard with two hexa-core processors running a total of 24 threads.

More than a decade or more past, I remember an article about a project for NSA, with parallel-processing and something like a hundred Xeons or other Intel CPUs all wired together. I think there were people involved who were students at MIT, but I can no longer be absolutely sure with precision.

 

[Kartajan]

SSD:
the 4 or 5 numbers in M.2 or NVMe "type" are size in mm.
example: 2280 is the typical "gum stick" size 22mm wide, 80mm long.

RAM:
Memory timing examples (CAS latency only)
Type Data rate Tx time Cmd rate Cycle time CAS latency First word Fourth word Eighth word
DDR4-3200 3200 MT/s 0.313 ns 1600 MHz 0.625 ns 14 8.75 ns 9.69 ns 10.94 ns
DDR4-3600 3600 MT/s 0.278 ns 1800 MHz 0.556 ns 17 9.44 ns 10.28 ns 11.39 ns

Transfer time = 1 / Data rate.
Command rate = Data rate / 2.
Cycle time = 1 / Command rate = 2 × Transfer time.
Nth word = [(2 × CAS latency) + (N − 1)] × Transfer time.

 

[anandtechreader]

Thanks. So, although the 3600 has higher clock, the end result is that the DDR4-3200 is actually faster since those values in ns are smaller. Is that right?

 

[Kartajan]

Assuming that your system will run the memory at its rated speed, yes.

 

[anandtechreader]

In practical uses, how is DDR4-3200 CL16-18-18-38 compared with 3200@CS14? I am going for the Z370 motherboard.

 

[BonzaiDuck]

At that speed, I'll ask my colleagues here if they want to apply caveats or beg to differ. But the differences are more relevant to benchmarking than to anything noticeable. Also, suppose you get yourself a G.SKILL TridentZ 3200 kit of whatever latency timings. If you only got a 2x16GB = 32GB kit -- two modules and therefore only two sockets occupied -- it is most likely that you can run those at command-rate = 1 instead of 2. I've always felt that CMD=1 was an easy "overclock" tweak that you could almost notice in effect for feeling "snappier."

If you socket all slots -- there should be a total of 4 on a Z370 motherboard -- it is less likely you could run at CMD=1, but I would try it, and I would try adjusting RAM voltage ever so slightly above 1.35V XMP (for instance, ~ 1.36V), and I would bump up the VCCIO/IMC voltage above its stock (Auto) value to some point below 1.2V, and less than the System Agent Voltage (VCSSA?), which should really be (at Auto) maybe around 1.23V.

Sometimes, the motherboard itself will auto-select CMD=1 for XMP-configured RAM for only two slots and two modules.

In principle, given the difference in prices, I would personally always opt for the kit with the tightest/lowest timings, and I would buy CAS=14 RAM over CAS=16 or 17.

I'm assuming that you are getting an ASUS Z370 board? Since you had focused earlier on the $500 X299 workstation motherboard by ASUS?

 

[Kartajan]

At that speed, I'll ask my colleagues here if they want to apply caveats or beg to differ. But the differences are more relevant to benchmarking than to anything noticeable.

I concur.

 

[anandtechreader]

The situation is that if I avoid buying from 3rd party companies, CAS=14 is available only from Newegg. If I go for Amazon, I have to choose DDR4-3200 CL16-18-18-38. I bought a computer case from Newegg. This is the first time I have bought anything from them. The box came in with a big hole and there is a big scratch on the glass. I asked Newegg to exchange a new one for me. They are giving me a hard time. First, they asked me to send them photos as evidences for "further investigation". Then, never heard from them since Friday. I am concerned about customer services of Newegg especially when things go wrong. So, I try to stay away from them. Can I deal with G. Skill directly if things go wrong? Is that a good company? I checked Corsair but they don't have DDR4-3200.

I read that spectre/meltdown patches have hugh impact on the performance of nvme m.2 SSD and a colleague mentioned that the performance drop could range between negligible to 20%. So, I don't want to spend a large amount of money on a system that has performance hit. I would rather wait for Cascade Lake that has the bug fixed at hardware level. Know when it will be out besides "second half of 2018"? I am also a bit concerned because some mentioned that it will support a 6-channel memory. Will my soon-to-purchase quad-channel memory become less efficient in performance if I use it in the 6-channel motherboard later?

Now, I am considering a temporary system as my current computer cannot get my work done. I am trying to decide between i5-8400 and 8700K. Any suggestion?

Is ASUS Z370 Prime A a good motherboard?

 

[Kartajan]

Asus is generally a good brand. Prime is their "entry Level" brand, whereas TUF is their "Reliability First" brand. I have no qualms about recommending either, as my experience has been great when it comes to their motherboards in general.

As far as 8400 vs 8700k; I have the 8400 myself (On an Asus TUF series board)- no issues for me.

Given a choice between 8400, 8700, 8700K- 8400 is cheaper (179 on amazon), 8700 is faster but more $ (299 on amazon), 8700K overclocks but even more $ (348 on amazon).
..Whichever one best fits the workload...
For comparison, the bitcoin miners say 8400 is fine...

 

[anandtechreader]

Thanks. For CPU, it will be either 8400 or 8700K. Save $ also on cooler if I buy 8400. If I buy 64GB RAM for this system now and Cascade Lake requires different RAM configurations to achieve high performance, I waste the RAM. If I buy 32GB now and I need more later, I may have RAM compatibility issues. Any suggestion?

Anybody bought G.Skill ram from Newegg? I heard that they are G.Skill's official dealer. Unless I go for a 3rd party unofficial reseller, can't escape from them if I want 3200C14. Don't know why Amazon does not like to sell 3200 @C14.

 

[Kartajan]

re: lack of c14 on amazon... I found a set of gskil c14 on my first try...https://www.amazon.com/G-SKILL-Flar...&srs=2529455011&ie=UTF8&qid=1524525570&sr=1-6
and if you are set on that brand but some other model, here is a g.skill amazon search...
https://www.amazon.com/s/ref=lp_252...00&h=7224a14128e5a02915cbd6316cc727bb603ade94

Unlike you, I have always had a good experience with the egg, both with g.skill (the ripjaws line usually has a good price) and other items, so YMMV...

Without any comparisons using your specific workload, I would likely go with 32G RAM and an 8400...

 

[BonzaiDuck]

I bought all my G.SKILL kits from the Egg, going back 11 years. I was always good about comparing resellers -- Provantage versus Egg versus CDW or MicroCenter. Egg always gives a competitive price, even if not always the cheapest option. But considering state taxes and shipping, getting Egg parts from City of Industry balances against ordering from some place in Florida like Tiger Direct.

Some people may have unpleasant experiences with Egg, but it never happened to me. I've had to RMA defective parts to them maybe two or three times. However -- G.SKILL support has always been the best. I've had kits replaced on their lifetime warranty in maybe a week's time. They even told me this time around that they "wouldn't support" two unmatched kits of the same TridentZ CAS 14 DDR4-3200 model because they couldn't guarantee they'd both run at spec speed and timings. They vouched to support two separate kits running at 3000 below their 3200 spec. But I didn't need that guarantee: they run at spec speed and timings filling all four motherboard slots.

If it's a matter of the current high price levels, it wouldn't matter getting them at Egg or somewhere else, like Amazon. Maybe here or there, you could save $10 or $20. But you wouldn't get free shipping.