Originally Posted by rui-no-onna
It doesn't need to be able to reach 1PiB. There are plenty of 120-128GB SSDs with MLC NAND that won't hit anywhere near 1PiB. As long as the Samsung 840 120GB can do 120TB (which means it meets Samsung's promise of 1,000 P/E cycles minimum
), it's good. I used 50GB host writes setting up a new PC with Windows 7. At that level of usage per day, the 120TB minimum
NAND writes will be used up, in what, 6.5 years? Most folks only write an average of around 5GB, at most 10GB to their SSDs per day. At 10GB/day, you'll use up the 120TB NAND writes in 30+ years.
There are plenty of TLC NAND manufacturers. The problem appears to be none have quite the same expertise as Samsung when it comes to controllers and firmware. Samsung really did something pretty amazing with Samsung 840 TLC. The only unfortunate thing about it is pricing.
The Samsung 840 tends to be more expensive compared to previous gen models with MLC NAND, particularly the Samsung 830 during all those clearance sales. The move to TLC NAND is designed to drive down prices. Unfortunately, prices were already down when the Samsung 840 was released. You see sales on previous gen 120GB MLC NAND SSD for $50-80 quite often, but the cheapest I've seen for the Samsung 840 120GB is $80 ($70 after $40MIR). Normally, it goes for around $100 or so. I've seen the Intel 330 and SanDisk Extreme 240GB for $140 on a couple of occasions but the lowest I've seen for the Samsung 840 250GB is $150. However, there have been some pretty good deals on the Samsung 840 500GB (B&H $300, Adorama $310).
Also, the fixed costs (packaging, chassis, PCB, controller, RAM, etc) for all the capacities should be the same so shouldn't the higher capacity models be cheaper per GB compared to the lower capacity ones? Why do 480/500/512GB capacity models often cost significantly more per GB compared to 240/250/256GB versions?
You are talking about special deals, not average or normal price. In China the 830's are skyrocketing in price, the 128's are already 1.5x the price of 840's. Only OEM ones can be bought for the same price as 840's but I would advise against them as their firmware can't be updated and Samsung's Magician doesn't recognise them as valid Samsung SSD's.
When I bought my 840 two weeks ago I bought it for 565 RMB, they are down to 525 already. The 250GB ones have dropped from 1100 to 950. By Summer there will be killer deals I hope!
Samsung 840 Day 47
Drive Hours: 1116
ASU GiB Written: 403,139.61 (393.69 TiB)
Avg MB/s: 101.97 (449.63 hours)
Wear Leveling Count (B1): 3232 raw (1 normalized)
Reallocated blocks (B3,05): 12 (99 normalized)
Failure count (B5, B6): 0 program, 0 erase
Uncorrectable Error Count: 0
ECC Error Rate (C3): 0
Looks like the wear is starting to show. Looks like the drive is retiring blocks without being an explicit erase or program failure (possibly excessive raw BER from worn cells). Will be interesting how much wear it can take.
However, it seems to have beat the Vertex 4 at endurance testing.
These 840's seem to have close to 3000 P/E cycles. I read somewhere a while ago that Samsung had boasted that their TLC chips had the endurance of MLC ones (can't find the link, claim may have been removed or I misread) and it seems to be correct. What I find interesting is how the drive is reassigning blocks without them actually being defect. However, 12 reallocated blocks at 400 TiB means they will easily last the PiB I am hoping for, meaning my drive will last me at least a decade even with the 24-30GB I write to it per day (average of 1GB/hour).
Edit: the 830 is, indeed, dead. I mistakenly thought there was a second one running but it seems I'm wrong.Edited by Liranan - 1/2/13 at 9:28pm