Can i upgrade the speed

It is possible but usually not worth the hassle.
Changing to another CPU chip that fits your motherboard may only show a 3-10% performance change.

See videos of CPU replacement in laptops like yours:

http://www.youtube.com/watch?v=aPdZ4PQhqyo
or
http://www.youtube.com/watch?v=I9a0hIPdVmc

In general, you are better off adding more RAM (memory) or replacing the hard drive with a faster SSD (Solid State Drive) to make a laptop "fly". Your laptop can hold a max of 8 GB RAM:

http://www.crucial.com/upgrade/Toshiba-memory/Satellite+C655+Series/Satellite+C655D-S5084-upgrades.html

In MOST laptops, slower 5400 RPM drives are used, and this is the main performance bottleneck. A 7200 RPM drive or (better yet) a SSD drive will help matters, as will more RAM (the most cost-effective speed increase).

Make sure the new hdd runs at least 5400 RPM. A 7200 RPM drive is a little better (or a Solid State Drive if money is of no concern).

For and external USB drive, the RPM is of no consequence. Internally it should only help speed up the access time, assuming it is the same type of drive.
Hope that helps.

Some laptops have "mobile" CPUs (physically smaller, and consuming less power) than the typical "desktop" CPUs.

So, if you know "how" to disassemble your computer, you may be able to remove the heat-sink & fans on top of the CPU, remove the CPU, and install a faster one.

However, if your current CPU is of the "Pentium III" series (which ranged from 500 Mhz to about 1400 Mhz), you may not be able to find a CPU that will be significantly faster than your current 1.26 Ghz CPU.

Instead, I would check the disk-drive -- if it is 4200 RPM or 5400 RPM, I would replace it with a 7200 RPM disk-drive, for better I/O speeds, and thus help your computer go "faster".

Also, I would add more RAM, again to make your computer go "faster".

250gb

Lacie drives have a 5400 RPM on there 160GB line nothing really changed until 500 GB to 1tB at 7200 RPM.

so the answer is 5400 RPM

Hope this helps please do rate and leave feedback.

Btw, I’m available to help over the phone in case u need at https://www.6ya.com/expert/edwy_1a56970cf1ea4620

Hello,
Acer aspire 7000 series you can upgrade the HDD till 160 GB SATA.

Thanks

Hello, Bob!

Seeing as I am a 6 year veteran of Dell Tech Support, I should be able to help you out, no problem.

One thing that I would like to let you know is this: according to Dell Support Policy, you ARE allowed to put a non-Dell-branded hard drive in your computer. However, if Dell Support deams that this non-Dell hdd has caused another Dell component to fail, they will not replace the defective product. BUT, since it is HIGHLY unlikely that a non-Dell hdd would actually cause any other failure, feel free to purchase a non-Dell hdd. (I often times suggested that customers take this route because unless you're purchasing a refurbished Dell product, you're only paying for the Dell name.)

Anywho...

There really are no limitations to what size hdd you can install in your computer. Of course, a larger hdd will take more time to process information (Basically, there's more surface area to scan when your computer is searching for a specific piece of information.). Your main thing will be determining if you have an IDE hdd or a SATA hdd.

The Dell Tech website CAN be your friend (support.dell.com). From there, you can view original configuration and even available upgrades simply by entering your service tag (Usually found toward the back of your computer, on a black sticker with white text. It should list your service tag, an alpha-numeric value, and express service code, an all-numeric value).

If I were in your position, I would most likely not go over a 160g or 200g hard drive... simply to keep decent performance.

Hope I helped!

• speed matters, too, and the quickest way to get a handle on speed is by asking how fast the drive spins. After all, a 7200 rpm drive has to move data faster than a 5400 rpm drive - or does it?

It's Not That Simple If you've been following the story over on Macworld about different benchmark performance between the 2.0 GHz white MacBook and the 2.0 GHz black one, you might be scratching your head. Except for the hard drive, the two 'Books were configured identically, yet some Speedmark results were quite different.
The MacBooks, like most computers made today, can ship with drives from any of a number of vendors, and Apple has made it easy to swap the hard drive in the MacBook. By slipping a 7200 rpm drive into the black MacBook, it came very close to matching the 5400 rpm drive in the white MacBook.
What's up with that?
My first thought was that perhaps one of the drives had a bigger cache than the other one. I've seen a big difference between 7200 rpm drives with 2 MB and 8 MB caches with my eMacs.
But as I read further, I saw that both drives had 8 MB caches, yet the 5400 rpm Seagate was edging out the 7200 rpm Fujitsu in several tests.
Digging Deeper In the world of notebook computers, 4200 rpm drives used to be the norm, and the first 5400 rpm drives provided a huge speed boost (they spin 28.5% faster). Jumping to 7200 rpm spun drives 1/3 faster than that, but that's not the whole story.
Another way to make drives more responsive is to add a buffer. In the ancient days of personal computing, drives simply read their data and dumped it over a bus to the computer as fast as they read it. Old timers may recall setting the interleave for drives used with the Mac Plus, SE, and II - and wonder why we no longer do that.
Setting interleave slowed down data transfer to a speed these old computers could handle, and then someone came up with the clever idea of building a data buffer (or cache) into the hard drive. Now the drive could read the data at full speed, store it in cache memory, and feed it to the computer at the top speed it could receive data.
And that's why one of my favorite Mac SE speedups is putting in an hard drive with a buffer to replace the ancient bufferless drives Apple used back in 1987.
And the bigger the buffer, the more data in the cache, the more efficient the process.
On top of this, there are different schemes for storing data in the buffer. A drive may look ahead a few sectors, or it may buffer the directory, or it may buffer writes, all of which can make things more efficient.
Physics That's drive electronics, and every brand has their own way of doing things. So you can see why a Seagate, Hitachi, or Fujitsu mechanism might offer different performance despite having identical spin rates and buffer sizes.
But there's a third factor beyond RPM and cache size - data density. Looking at the manufacturer's specs for 5400 and 7200 rpm 2.5" Seagate Momentus and Hitachi Travelstar drives, you'll see that the transfer rate of the 7200 rpm drives is less than 1/3 faster than the 5400 rpm drives - just 9% faster for the Seagate, and a more impressive 28% faster for the Hitachi.
The big breakthrough over the past year or so is perpendicular recording, which can easily store 50% more data per track. Just how much data is there per track? That's hard to know, in part because the manufacturers don't promote the number and also because the amount of data stored per track varies between the inner and outer tracks of a drive platter.
Still, if Drive A spins at 5400 rpm and stores 40% more data per track then 7200 rpm Drive B, it will be able to read more date per second. That might help explain how a 5400 rpm drive can sometimes outperform a 7200 rpm one.
Conclusions Tech Report has an extensive article comparing these four drives. It looks at peak transfer rate, how well each drive handles multiple data streams, and typical read and write speeds. And just as Macworld discovered with the MacBook and both brands of drives, Tech Report says, "At times, those performance differences were surprising, as we certainly didn't expect to see Seagate's Momentus 5400.2 beating Hitachi's Travelstar 7K100 in so many tests."
Various drive parameters can be tweaked, optimizing a drive for use by a single user or in a server, even optimizing for the way an operating system works and how many data streams it may work with at any given time.
In the end, there's more to picking a hard drive than capacity, rotation speed, and buffer size. Seagate, Toshiba, Hitachi, and Fujitsu each have their own buffering algorithms and optimization schemes, so you'll want to look for benchmark results using the hardware and operating system you'll be using. (OS X on Intel Macs may produce very different results than OS X on a G4 or G5 system.)
Price is the final factor (after all, Low End Mac is primarily about value). If ultimate performance isn't crucial and the 5400 rpm drive is a lot less costly, it may well be a better choice for you. But in the end you have to come up with your own value equation - how important is capacity vs. performance vs. price?

In your laptop you cant upgrade your hard drive. Go for the web search for upgrade options , try it in sony web site please inform to fixya.com for any other porb.