Question Good inexpensive 2.5" 250GB SSDs (with RAM)?

[sheh]

AnandTech didn't review the Crucial MX500 250GB so it's difficult to compare.
Tom's Hardware compared against other models than those below.

500GB models would be a much better choice but cost-consciousness is a big factor.
Older 250GB models (MX200?) would likely be better due to more flash channels or MLC, but the market has moved on.

I'm ignoring: DRAM-less, QLC, models with unknown specs or from lesser brands, Samsung (much more expensive), SanDisk Ultra 3D (somewhat more expensive), Intel (more expensive with apparently no benefit).

WD Blue is generally similar to the MX500, maybe uses less lower power. Haven't checked thoroughly yet but I expect the Seagate Barracuda to be somewhat slower.

So far I'm left with ADATA SU800 ($34), Hynix S31 ($30), Crucial MX500 ($39).

SU800

+ Mostly quicker than S31 (bench), sometimes by much
* 200 TBW
- Doesn't manufacture own flash
- 3 years warranty

S31

- Mostly slower than SU800, sometimes by much
* 200 TBW
- Relative newcomer in the retail market, so no long-term info on reliability
+ Manufactures own flash (+controller)
+ Newcomer, so needs the support
+ 5 years warranty

MX500

(Compared to test group on TH, which notably includes the BX300 and Samsungs, but not the above two models. But if the 500GB models are an indication, should be quicker than the above two.)

- Steady-state sequential mixed - somewhat slower
- Steady-state 4K random - generally slower
- PCMark 8 "advanced workload" - slowest, in some tests notably (like "Recovery")
* Okay in other tests.
- 100 TBW
+ Veteran player, manufactures own flash
+ 5 years warranty

 

[Insert_Nickname]

I'm ignoring: DRAM-less, QLC, models with unknown specs or from lesser brands, Samsung (much more expensive), SanDisk Ultra 3D (somewhat more expensive).

Cheap generic SATA drives I can understand avoiding, but DRAM-less and QLC*? Why? Even those are very close to totally saturating the SATA interface itself. That's the bottleneck, not the controller/flash combination itself.

Performance? NVMe drive, no question. SATA drives have been relegated to cheap storage. For a system drive, any SATA drive on the market will still give acceptable performance with consumer workloads. Yes, even the BX500 128GB, which is about as cheap as you're likely to get.

*There aren't an awful lot of QLC SATA drives currently. The 860QVO is the only prominent one.

 

[sheh]

SATA satuaration happens only in ideal test cases, such as sequential I/O on an empty drive.

Random I/O, small blocks, "wrong" queue depths or read/write mixes, all lead to much worse performance, which doesn't saturate SATA (also true in more expensive drives). There's possibly also more write amplification when there's no RAM.

Two random examples. BX500 250GB (and TR200) vs MX500, from TH:

"DiskBench" copy rate, 68MB/s vs 131MB/s (which makes the BX500 closer to an HDD than it is to the MX500):

Sequential steady-state write, ~100MB/s vs ~200MB/s:

120GB would be worse since there's even less flash parallelism.

BTW, about QLC, another reason to avoid is probably worse retention.

 

[VirtualLarry]

*There aren't an awful lot of QLC SATA drives currently. The 860QVO is the only prominent one.

Adata SU630 is QLC and SATA 2.5" too.

Edit: BTW, OP, I've heard that the BX500 is DRAM-less.

OTOH, Silicon Power's A55 "Ace" drives, are advertised with DRAM and SLC cache. I've used those before, and they are both inexpensive, and good performers (well, among budget drives, they're still no Samsung EVO).

 

[sheh]

OP, I've heard that the BX500 is DRAM-less.

Yep. I mentioned it to show DRAMless performance compared to the MX500.

Silicon Power's A55 "Ace" drives, are advertised with DRAM and SLC cache.

I saw them, but didn't find in-depth reviews, Silicon Power isn't too well-known, there aren't full specs anywhere (e.g., TBW), and in fact it appears the A55 hardware has changed or is just variable.

In one 2017 review it was the DRAMless SM2258XT + Intel flash. In a 2018 review it's Phison S10 + DRAM + unknown rebranded flash. The 2018 version is probably a Phison reference board, as it's the same PCB and components as the Gigabyte UD PRO SSD, and also very similar to the Corsair Force LE and PNY CS 1311.