Thought I'd put this up here for those encountering poor performance on their SSD's, there are several causes for low read/write speeds.
If you are having problems, take a look over the following suggestions
1. Are you plugged into the highest speed SATA port?
(Note the difference - Gb/s is Gigabits per second, GB/s is Gigabytes per second, there are 8 bits in one byte)
If it is plugged into a SATA I (standard) port, the max transfer is 1.5Gb/s, due to overheads this is reduced to 1.2 Gb/s. This equals around a 150MB/s throughput.
SATA II ports can reach around 3Gb/s, minus overheads at 0.6Gb/s, equals 2.4 Gbit/s (300 MB/s throughput).
This leaves a SATA III transfer rate of 6Gb/s, minus overheads at around 1.2Gb/s, equals 4.8Gb/s, leaving a throughput of around 600MB/s.
If your motherboard has the capability of supporting SATA III, you should connect your drive to this. Some motherboards have several SATA III controllers. Read more below.
2. Are you plugged into the best SATA controller?
Many motherboards have several SATA controllers. For example, take this X79-UD5 Gigabyte motherboard HERE, you can see it has 10 SATA ports, with colours denoting each set. In the spec sheet (HERE) you can see it shows that there are 2x SATA III ports (white in the picture) controlled by the X79 chipset, and 4x SATA II ports also controlled by the X79 (black in the picture). The SATA III ports attached to the Intel chip, in this case, will provide the best throughput for connecting your devices.
However, also on this motherboard are Marvell SATA controller chips. These control 4x SATA III ports (grey in the image), which are 'rated' at 6Gb/s, but in reality are slightly less, at around 5Gb/s (about 3.8 after overheads). A true 6Gb/s port will give you around 600MB/s throughput, however on third party controllers, you often find the max you can reach is around 475MB/s (it can differ). There are other manufacturers who also provide controller chips, ASMEDIA for example.
In order of priority (depending on what you have available), you should be plugging into SATA III controlled by the Intel chip first, then onto the third party SATA III ports (Marvell in this case), then the Intel SATA II ports.
If you have no SATA III ports on your motherboard, or only have a third party controller, you could always purchase a seperate PCIE card to attach them to, however I don't advise this as you won't notice a huge jump in speeds (unless coming from SATA II). I would suggest sticking with the third party controller if you have them on your board and upgrade when you get the change and are perhaps swapping out your CPU as well. It's probably not worth buying the controller card for the stop gap in between.
3. Are you running the drive in AHCI mode?
There are several ways your system communicates with your drives, the older IDE system (Legacy/Native), AHCI and RAID.
IDE is what most older systems will run on, and more often than not can be enabled as default. You want to be running in AHCI mode.
BE AWARE if you switch to AHCI without applying this fix HERE then your drive may fail to boot back into windows.
Please apply the fix before restarting to enabled AHCI in your BIOS.
You will have to refer to your own motherboard's manual with regard to locating the AHCI option in your BIOS. It is more often under a 'Peripherals' section of your BIOS.
4. Have you got the latest firmware on your drives?
Most SSD's have a firmware section of the drive, for instance my Crucial m4, advertised at 128GB, is actually only 120GB, as the extra 8GB is used by the drive as a firmware portion and partitioned off. This is not visible to you though.
Firmware is what makes the drive actually run. It's a combination of software and hardware that work together to make devices work. Quite often there are methods in place to update your drive's firmware.
Just for reference, here's a link to several of the SSD manufacturer's site's from drives sold here on Aria. It's always advised to update to the latest firmware, be wary though it MAY wipe the drive and sometimes brand new firmware releases can be a little unstable and have certain issues with updating.
Some useful programs to use in conjunction with your SSDs
AS SSD (Benchmarking)
Intel Rapid Storage Technology (Only for use with the correct hardware and beneficial in RAID systems)
If you have tried all of the above and your drive is still experiencing slow performance, put a thread up here in the forums or head to the manufacturer's forum to see if there are others with your issue.
If you have anything you'd like adding to the above post, don't hesitate to ask!
Possible sticky? Might be useful for others (that's assuming I got it all right).