Key takeaways
- SSD gives you performance, HDD gives you capacity per dollar. For the machine you actually trade on, performance is the one that pays.
- An HDD stores data on spinning magnetic platters read by a moving arm, at 5400 or 7200 RPM. An SSD uses flash memory with no moving parts at all.
- The speed gap is not subtle: roughly 50 to 120 MB/s for a mechanical drive against 2000 to 5500 MB/s for a solid-state one.
- Moving parts are the weak point. Mechanical drives are likelier to fail, run hotter, draw more power, weigh more and make noise.
- Cost per gigabyte still favors HDD — around $0.03 against roughly $0.20 — which is why bulk archive storage remains a reasonable use for one.
- For a trading laptop, solid-state only. There is no case for a mechanical drive in a machine that moves.
- The practical setup for a desktop is both: the SSD holds Windows, your platforms and anything in current use, and a larger HDD holds archives and recordings.
- Only consider a mechanical drive as primary storage if you genuinely need more than about 3 TB, where solid-state pricing climbs steeply.
- Not sure where your machine stands? The free benchmark test takes about two minutes.
A Brief History of HDDs
Hard disk drive (HDD) technology has been around since the beginning of modern computers. In 1956, IBM shipped its RAMAC 305 system with only 5 MB of hard drive capacity. At the time, each megabyte of data cost $10,000. The first IBM PC to have a hard drive (in 1983) came with a 10 MB drive that cost less than $2000 (or $200 per MB). The entire computer cost $5,000. Of course, HDDs have come a long way. The HDD technology has gotten better and cheaper. Today a 500 GB hard disk drive, standard in most computers, has 500,000 MB and costs around $50.How HDDs Work
Hard disk drives use spinning magnetic disks or platters to read and write data. Platters in most off-the-shelf trading computers have 5400 RPM or 7200 RPM speed. (RPM stands for Revolutions Per Minute.) Faster speed means faster access to data. HDDs can have one or more platters. Each platter has an associated actuator. The tip of the actuator arm has a magnetic head that can read and write data to the magnetic platter. A way to visualize an HDD is like a vinyl (record) player.HDD Pros
- Proven technology that has been around for 50 years
- Less expensive at around $0.03-per-gigabyte
- Better security provisions for encrypting your data
HDD Cons
- Due to the physical spinning of the platters, data reads and writes take longer (50-120 MB/s)
- Mechanical parts of the device have a higher probability of failure
- Heavier than newer technology
- Power consumption is high
- Spinning platter creates a noisy environment and produces heat
A Brief History of SSDs
You might be surprised to learn that SSDs had their origin in technologies developed in the 1950s. The first commercially available SSD (the Bulk Core by Dataram) measured 19” wide by almost 16” tall. A setup with 256 KB of storage sold for $9700 in 1977 (or around $38,000 per MB in 1977 dollars). The modern flash drive didn’t appear until 1995 and was so expensive it wasn’t used much outside of military and aeronautical applications. Reasonably priced consumer models came along in 2003.How SSDs Work
Solid state drives are nonvolatile flash memory. They use microchip technology. There are no mechanical parts. Data is stored on floating gate transistors using electronic charges. SSDs read and write data using an embedded processor called a controller. Due to the absence of moving parts, access to an SSD drive is faster. The data is stored in rows and columns which are divided into blocks. The controller charges and discharges the floating gate transistors to store information. An easy way to visualize an SSD is an ice cube tray. Think of the filled slots as charged and empty slots as discharged transistors.SSD Pros
- Fast data access (2000-5500 MB/s) means faster boot-up and better performance
- Consumes less power and produces less heat
- No noise during operation
- No moving parts = longer life
- Lightweight
SSD Cons
- More expensive at around $0.20-per-gigabyte
- Most trading computers with SSD will come with less storage capability
Comparing SSD vs HDD for Your Needs
From the above discussion, it’s evident that SSD gives you performance while HDD saves you money. For a trading computer you use regularly, SSD is a better choice. It will provide faster performance, so the investment is worth it. You can easily find computers for trading that have 500 GB 1 TB SSD drives. However, if you are buying a computer to store large amounts of data (>3 TB), an HDD drive will probably make sense. Otherwise, you will end up paying a huge premium as SSD drives get pricier with larger sizes. The third option is to get a trading computer configured with both types of drives. Store your archival files on the larger HDD and store files in current use on the faster SSD. It’s the best of both worlds.Conclusion
Before deciding on which drive type (HDD vs SSD) is best for you, consider how you use your trading computer. For trading laptops, we definitely recommend a solid state drive. For trading desktops, you can get away with an HDD, but an SSD will give you better trading performance. Many traders like to have both types of drives on their desktop trading computer. There are more trading computer tips like this in our EZ Trading Computer's buyer's guide. Check out our "How To Buy a Trading Computer" e-book. Remember, we are here to help with all your technology-related questions. If you think of additional questions about computer hardware or other questions, give me a call. My team and I are here to help. We're happy to answer any of your questions about trading computers via phone: 800-387-5250.Frequently Asked Questions
SSD or HDD for a trading computer?
SSD for anything you actually trade on. The difference in access speed is between roughly 50 to 120 MB/s on a mechanical drive and 2000 to 5500 MB/s on a solid-state one, and that shows up as boot time, platform load time and how the machine behaves under pressure. Keep an HDD only as secondary storage for archives.
Is it worth having both an SSD and an HDD?
For a desktop, often yes. Put Windows, your trading platforms and current working files on the SSD, and use a larger mechanical drive for archived data, screen recordings and backups. You get solid-state speed where it affects trading and cheap capacity where it does not.
How much faster is an SSD than a hard drive in practice?
Boot and load times are the obvious difference — seconds rather than minutes — but the part that matters for trading is behavior under load. A mechanical drive has to physically move a head to reach data, so when several programs demand data at once, requests queue. A solid-state drive has no such limit.
Do trading laptops need solid-state drives?
Yes, without exception. A laptop moves, and a mechanical drive contains a spinning platter and a head suspended fractions of a millimeter above it. Beyond the speed argument, it is the fragility that rules it out. Every current trading laptop should be solid-state, and ideally NVMe.
When does a hard drive still make sense?
When you need bulk capacity above roughly 3 TB and the data is not in active use. Solid-state pricing rises sharply at large sizes, so archives, video and long-term backups are all reasonable uses for a mechanical drive. Just keep it out of the path between you and your charts.
