Hi Angus.
I wrote that quite late at night after some loopy juice had been consumed.
Not saying I retract it though, had I been more inclined I would have gone into more technical detail - but Friday nights are usually a blur due to the efforts of the week and a drop or two!
So here you go, this is my reasoning:
SSD data is divided into 'pages' and 'blocks'.
A single page is the smallest chunk that can be written to or read, usually 4K on a Windows system (the default NTFS size) so a 1KB file will take 4KB of disk for exclusive use.
A block is 128 pages usually on an SSD.
When changing the contents of a single page you have to erase the entire block (all 128 pages) and then write it back with the changes required, this is half a megabyte of data change for a 1KB file change.. ouch.
Upshot is that just changing 1KB of date means the disk has to process half a million bytes - read and then write back each one so a total of 1 million bytes of transfer is done.
Actual figures are for a 1KB write a total of 511,999 bytes are erased and rewritten 'write amplification'.
In read only scenarios an SSD leaves mechanical in the dust, but you have to consider what the read and write characteristics profile your system will employ.
For streaming video, fantastic.
Photo editing.. pretty good but an overhead when you write back the edits, offset by the sheer number of pages that will be written back.
Games..
Loading will be supremely fast.
But what write operations do the games need to do as part of their operation?
All write-backs will suffer a performance hit as they are likely to be small (sub half meg) data changes that carry a high write amplification overhead.
SSDs fall behind on non-sequential operations on small files.
Example of Samsung Spinpoint F3 vs Intel 510 SSD:
The F3 tops 80MBs on random reads and comes in at 4.5p per gigabyte.
The 510 manages 20MBs and comes in at 183p per gigabyte.
Upshot is SSDs are great fr large files, but for day to day Windows operations in a consumer setting they will not carry as much benefit.
Many have invested and claim great benefits, I would not personally admit my $200+ investment failed
Reuters have trialled Enterprise class SSDs, and for now stick with mechanical drives because of the performance issues, and we are very hot on lowering latency for obvious reasons!