Question DRAM cache SSDs

Pupq1

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Jun 6, 2019
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In what scenario is an SSD that has DRAM cache useful? And how do I know that an SSD has DRAM cache?
 
it's where the writes are stored prior to being written, hence it provides speed for a limited number of writes at RAM speeds (V fast). Dramless uses a portion of the drive as that cache which isn't as fast as RAM, and causes more wear on the drive, and will mean that as the drive fills it will slow down as it gets close to being full.
 

Pupq1

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Jun 6, 2019
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wouldn't help a CPU. Anyone that writes to disk a lot, would do better with a dram cache SSD. To find out which read the reviews, when you look at charts in the reviews you'll be a big gap between the two types.
I can't find such type of charts for the Kingston A400, could you look it up please
 
It states quite clearly here: https://www.hardwaresecrets.com/kingston-a400-120-gib-ssd-review/
that there are no cache chips. It's not common for them to come explicitly an say whether it does or does not have dram. Tom's reviews will often say it, but they've not reviewed it.

Note here: https://www.tomshardware.com/reviews/crucial-bx500-ssd,5377-3.html
in the performance line graphs, you'll see when it's cache gets filled and perf drops off.

On another note you do realise that we are volunteers here, asking us to search for stuff, or read stuff for you will generally get you nowhere.
 

Pupq1

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Jun 6, 2019
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It states quite clearly here: https://www.hardwaresecrets.com/kingston-a400-120-gib-ssd-review/
that there are no cache chips. It's not common for them to come explicitly an say whether it does or does not have dram. Tom's reviews will often say it, but they've not reviewed it.

Note here: https://www.tomshardware.com/reviews/crucial-bx500-ssd,5377-3.html
in the performance line graphs, you'll see when it's cache gets filled and perf drops off.

On another note you do realise that we are volunteers here, asking us to search for stuff, or read stuff for you will generally get you nowhere.
First of all, I'm really sorry for wasting your precious time reading a review 😂
I did look through some reviews but I didn't find the info
So right now I have an Acer ES1-532G laptop that has a Pentium N3710 quad core cpu that boosts to 2.56ghz, 8gb of ddr3 ram at 1600mhz and a 920mx gpu (see, I wrote all these specs so you don't have to search them on google) and a slow 5400rpm hdd which I wanna replace
I use it mainly for gaming and I'm buying the ssd for shorther load times and overall better system responsiveness and I wanted to know do you think the kingston would make it or is there any point in buying one that has DRAM cache
Thanks
 

popatim

Titan
Moderator
A400 would require a fresh new installation of Windows. It does not have 512byte emulation and only uses 4k size.
If you plan on cloning get an Mx500, 860 Evo, Wd Blue 3d (usually not listed as 3d so make sure it says it on a pic of the label), or Sandisk Ultra 3d would be my choices.

These drives use a dynamic method of caching the writes which uses the 3D TLC flash in SLC mode. So as long as there is adequate room on the drive, you will have good write performance. Just make sure you leave empty space on the SSD for this and other internal housekeeping tasks (such as garbage collection).

Dram is only good for large writes and dynamic SLC mostly eliminates the need for it.
 
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Pupq1

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A400 would require a fresh new installation of Windows. It does not have 512byte emulation and only uses 4k size.
If you plan on cloning get an Mx500, 860 Evo, Wd Blue 3d (usually not listed as 3d so make sure it says it on a pic of the label), or Sandisk Ultra 3d would be my choices.

These drives use a dynamic method of caching the writes which uses the 3D TLC flash in SLC mode. So as long as there is adequate room on the drive, you will have good write performance. Just make sure you leave empty space on the SSD for this and other internal housekeeping tasks (such as garbage collection).

Dram is only good for large writes and dynamic SLC mostly eliminates the need for it.
No, I don't plan on clonning since my laptop has a single SATA port. I'm fine installing everything again and my files are on a flash
The reason I was looking for DRAM cache is that I thought that, in my case it would be a better one. My cpu is the big botteneck of the laptop and I thought a DRAM SSD would help and overall would perform better than a DRAM-less SSD.. Isn't that true?
I don't quite have the money for a high-end ssd like the ones you mentioned, since their 240gb versions are more expensive than the 480gb versions I'm looking at
So I'm loking at a Patriot Burst 480gb which has 32mb of cache and it's the same price as the A400 (about $50) would that be a good choice?
 
These drives use a dynamic method of caching the writes which uses the 3D TLC flash in SLC mode. So as long as there is adequate room on the drive, you will have good write performance. Just make sure you leave empty space on the SSD for this and other internal housekeeping tasks (such as garbage collection).

Dram is only good for large writes and dynamic SLC mostly eliminates the need for it.
Thanks, this explains a lot.

Here is another DRAM-less SSD:

https://forum.hddguru.com/viewtopic.php?f=10&t=38633

The SSD's capacity is 120GB, yet all my searching suggests that its single NAND flash IC (29F01T2ANCMG2) has a capacity of 192GiB. That's a helluva lot of overprovisioning. However, it all starts to make sense when you think about dynamic SLC cache.

BTW, Phison's web site confirms that the Kingston A400 controller (CP33238B aka Phison PS3111-S11) is DRAM-less:

http://web.archive.org/web/20170719133119/http://www.phison.com/English/ICSpeed.asp?SortID=63
 
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Pupq1 asked: ".. ......how do I know that an SSD has DRAM cache?"

I have maintained an ad free, public service, ssd database for over 10 years now. Earlier this year, individuals asked me to include information about DRAM in the database. When I started to update the ssd database I made several discoveries:

1. 99% of the newest retail solid state drives have some sort of DRAM used as a cache.

2. There is only a very very small handful of mainstream, retail PCIe, NVME, solid state drives that do not have a DRAM cache. They are equipped with either a Silicon Motion SM2263XT (or older version SM XT) controller or a Realtek RTS5763DL controller. I have not yet encountered any other ssd's without DRAM that did not have one of the two controllers. That may change because I am still trying to locate additional information.

3, Information about DRAM is a new phenomenon. Older product specifications and technical reviews do not include the information.

[U]popatim[/U] - ^5 It has been a long time!!!
 
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