Are SSDs faster than physical RAM?

gorskiegangsta

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Oct 2, 2013
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No, not even close.
DDR3-1600 RAM has bandwidth of 12.8GB/s, while SATA3 SSDS max out at ~550MB/s, making them at least 25x slower. Faster (and more expensive) PCIe SSDs are able to get to 1.2GB/s, which is still over 10x slower then RAM.

The reason for this is that as users began to demand increased storage capacity for their digital files and as the OS/software began to evolve rapidly, in order to save costs and bring prices down, the industry decided to segment computer memory into higher quality, faster, low(er) capacity, more expensive, volatile storage (RAM), and slower, cheaper, more dense, higher capacity, non-volatile memory (started with "read only memory" ROM chips in the early days, then moved on to platter hard disks, now to solid state drives). As it stands, these are two different types of memories, designed for different things. To simplify it, think of RAM as computer's short-term (i.e. disposable) memory, and storage (be it ROM, an HDD, or an SSD) as long-term (i.e. retained) memory.

If you look closely, you'll see that RAM is way more expensive $/GB than even the most expensive consumer SSDs ($1.2/GB for some Intel drives). 16GB DDR3-1600 RAM still costs $100+, which is $6.3/GB. For a more stark comparison, a 128 SSD can be as low as $90 whereas 128GB of RAM will cost you a hefty $800+.
 

Muneeb Ahsan

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That's what i want to hear, thanks for your quick and complete answer. here's one thing which i want to mention here, Ram disk, are best to use or not? i know the rams are volatile besides of this , are ram disks best to achieve rocket boost speed?
for ram do we have to have faster rams or the simple rams even can defeat ssds in performance? and which software do you recommend for to make ram disk, please mention the name of free one :) ....
 

gorskiegangsta

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Depending on your uses and needs, RAM Disk may, or may not, benefit you. If you have RAM to spare (8GB+ recommended) then you can allocate some of your RAM to use as RAM Disk, in order to speed up some applications.
The most recent RAM Disk software I tried was made by AMD. I believe it is free for creating up to 4GB RAM Disk (6GB for AMD memory).
http://www.radeonmemory.com/software_4.0.php

For comparison, here are benchmark results comparing HDD to SSd To RAM Disk:
xtreme_comparison.jpg

The HDD is being ran at RAID10, and the figures for SSD are a little outdated, but you get the idea.
 

fissionflame

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Ram will always be faster than a SSD if you keep Raid out of the picture. The reason for this is because both an SSD and Ram are using the same concept of no moving parts, store in cells idea. Here is where the difference = speed. A SSD is a long term storage device. Its meant that if you power down the computer, then power it back on, the memory inside it will be intact. This requires a more complex method to keep your data. Ram on the other hand is suppose to dump all its storage upon powering down the PC. This means that it doesn't require the complexity of storage without power.

Lets also compare the 2 SSD types.
There are Multi Cell and Single Cell SSDs available. Consumer level uses Multi Cell while Single Cell is exclusively for enterprise solutions.

lets compare the 2 with set values.
a Consumer SSD has the following
500MB/s Write
500MB/s Read
1,000,000,000 Reuses per cell.

If the company made the same SSD but as a Single Cell, it would show this:
800MB/s
800MB/s
3,500,000,000 Reuses Per Cell.

The reason for this is that a Multi Cell SSD can store the following, 00, 01, 10, 11. A single Cell only stores, 0, 1.
Since the multi cell is capable of 4 possible choices, it requires a more complex algorithm to do the same job, but it also requires less space thus taking less time to build.

If you were running 4 state of the art single cell SSDs in raid 10. you would get fairly close to the results of doing a RamDisk with high end memory. Unfortunately though SSD technology is still too new and would cost way more than it would to invest in top quality ram and just RamDisk what you need to. I personally RamDisk my games but the actual RamDisk only has a copy and i just extract any save data if the game updates like that.