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Thread ID: 122255	2011-12-11 21:05:00	Is SDD faster than HDD	lostsoul62 (16011)	Press F1

Post ID	Timestamp	Content	User
1248187	2011-12-11 21:05:00	I have a SATA 3 WD 1TB HDD that is 6Gb/s and if I buy a SSD it is also rated at 6Gb/s however the SSD cost 10 times more for each byte so what am I missing?	lostsoul62 (16011)
1248188	2011-12-11 21:53:00	You would be missing that BUS speed does not equal data transfer rate, 6GB/s is the maximum the SATA 3 BUS can handle, not the speed the HDD is transfering data at.	Alex B (15479)
1248189	2011-12-11 21:58:00	The HDD won't reach those speeds. SATA3 has a max speed of 6GB/sec, that's all that the HDD is saying, that it supports the SATA3 spec (As SATA2 has a limit of 3GB/sec). That, and in terms of random reads / writes, the SSD will leave the HDD for absolute dust! Lets say you're looking at this one: www.wdc.com IIRC they have a sustained transfer rate of around 150MB/sec (Roughly). Grab yourself a SSD like this: pbtech.co.nz( It will absolutely *blitz* it! This will give you a good example, read this, and the next page: www.guru3d.com	Chilling_Silence (9)
1248190	2011-12-12 21:46:00	I'm confused because both drives are rated at SATA3/6Gbps but one is much faster than the other but I can't figure out why since their rated the same?	lostsoul62 (16011)
1248191	2011-12-12 21:53:00	They work off the SATA3/6Gpbs ports. The ports/controllers or whatever they run off can transfer at a maximum of 6gbps. The hard drive or ssd doesnt actually transfer at that rate.	icow (15313)
1248192	2011-12-12 21:54:00	I took a look at some other sites and posts and it's partly about access time and so forth so I think I'm understanding better and will get a 60 Gig SSD for my OS, Thanks	lostsoul62 (16011)
1248193	2011-12-12 22:11:00	Not just access time, but actual throughput. It's like saying that the Auckland Dam can pump out 370 million litres a day, that doesn't mean that your house can receive it that fast. Same for the connection from your PC to your Router. It may be able to run at 100mbps, but because your router only connects to the internet (The router being a slow HDD), you only get around 10mbps. If you had Fibre (The Fibre being a SSD), then you'd be able to reach much closer to that 100mbps. So just to clarify: In this case, the SATA cable is fast enough to receive at up to 6gbps, however the HDD can only read and write at around 150MB/sec. The SSD is able to read / write at around 475+MB/sec. Add on to the fact that it's able to read / write from multiple places at once a lot better than the HDD (Because the HDD has a moving head) and you'll see the difference matters ;)	Chilling_Silence (9)
1248194	2011-12-13 01:03:00	Yes pretty much answered but I thought I'd add the SATA 6gbps is not a performance rating of the drive but rather as people here are trying to point out the maximum speed of the port it connects to in the PC. To get an actual rating you would need to look up the specifications of the particular drive. The two technologies are very different, SSD has no moving parts and HDD is spinning platters of magnetic material. Because a normal hard drive has to physically locate data when you access it it has a "seek time" rating which tells you how long on average it takes to start transferring. An SSD also uses this rating but is generally MUCH MUCH faster at this which makes them excellent at finding and loading lots of little files - like when windows boots up.. Then there's the transfer rate - how fast it goes once it finds the data. A good HDD can burst over 200MBs and sustain over 100MBs. A good SSD currently is hitting around 500+ MBs sustained and a slower model like mine around 200MBs sustained. There are some cheaper models that write slower than a normal HDD and read at about the same average speed. For the most part though SSDs are a huge improvement over normal HDDs.	dugimodo (138)
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