Replacing hard drive with compact flash cards

[JON999]

Considering replacing hard drive by putting in 2 compact flash cards via a IDE to dual flash adapter, allowing card to be bootable and using them as master/ slave. This would allow me to have a totally quiet pc.
I only really use ms office (usually word) and explorer so I was thinking of putting windows on one card and office on another.
Can currently buy 512mb compact flash cards for £99 each, but I think I would at least need dual 1gb cards, so I will wait for the prices to come down.
has anyone done anything like this? I would be interested to know how you got on.
and do you think this would work ok? would appreciate any comment on this.

thanks
jon

[Jan Kivar]

IIRC those flash mems have really low "write counts" (something like 10000+ times only). I mean how many times one can write to the same "spot" in the card. After that the "spot" is like a bad sector. This isn't really a problem with digicams and mp3 players. Windows' swapping will kill the flash cards quickly.

Plus, the cards are too small. 512 MBs can probably hold Win9x, but is too little for 2k/XP (i'm not sure whether 2k/XP would even install, because of low disk space). 1 GB card could be enough.

Cheers,

Jan

[ghowarth]

www.minibox.com supply midget pcs that use a compact flash card like this. I considered doing it myself, but I need more filespace, not less It would be quite funny to get a RAID of 2 CF cards running *lol*

Cheapest UK place I found when I was looking around for CF cards is www.komplett.co.uk . I'd be interested to know the difference in speed a CF card makes to a system instead of a hard disk - I'd imagine it would be somewhat slower. Let us know about that, if you take the plunge!

[JON999]

Thanks for the advice

Jan Kivar – I didn’t know about the low ‘write counts’ , I guess this would permanently damage the card, out of curiosity how long do you thing it would take?
I know there are other commercial solid state hard drives, do they use better flash memory or something? I suppose that’s why they cost so much.

Also a lot of the compact flash cards have five year replacement warranty and 30-day money-back guarantee, so if the cards only went bad after a while you could send them back.
Well it seemed like a good idea at the time.

Ghowarth- thanks for the links, I can’t get the minibox one to work though, how do the midget pcs use flash memory? Instead of a hard drive? How do they get around the ‘write counts' problem’?
I’m also not sure how fast it would be when connected to an ide connector
Looking at prices for cf cards I notice they are now selling 2gb cards, cost a fortune though

Thanks
jon

[Ducky]

Thanks for the advice

Jan Kivar – I didn’t know about the low ‘write counts’ , I guess this would permanently damage the card, out of curiosity how long do you thing it would take?

100,000 writes per memory cell, after which they become read-only. The "weakest link" in a typical file system is the file table. So, depending on how much you write to your cards, it'd take different amounts of time to die.

I know there are other commercial solid state hard drives, do they use better flash memory or something? I suppose that’s why they cost so much.

I believe those cost so much because it has exactly the same amount of RAM as its solid state storage, so it loads everything into RAM at boot-time, and only write back to the hard drive if the power gets turned off.
Some even has external AC power, and only saves when it goes on its emergency battery power.

So, those can actually last 100,000 or more shutdowns.

Also a lot of the compact flash cards have five year replacement warranty and 30-day money-back guarantee, so if the cards only went bad after a while you could send them back.
Well it seemed like a good idea at the time.

Yes, when it fails and you notice, you can probably exchage them for new ones, as long as you can accept that some files may be corrupted at that point.

Speedwise, they're actually ridiculously fast on reads (no seek time!), though the transfer rates suffers somewhat because it only supports PIO mode 4.

If you want a "bigger" compactflash compatible card, why not try a IBM/Hitachi Microdrive? They're cheaper per MB and just about as quiet. The only reason against using them is if you plan on using your computer in very humid conditions. (e.g. Steam from hot water -- say, at a hot spring or steam room, reportedly kills Microdrives.)

[lenny]

Compact flash are much slower than hard disks. It's fine it you're using it to load the OS and some application, but not if you're using it as a hard disk replacement.

Check http://www.dpreview.com/articles/mediac ... ead#fwperf for speed comparison of some compact flash cards. This is using a firewire reader. I've not been able to get close to that speed with my Viking 512MB using USB 2.0. Maybe IDE may improve the performance, but I doubt by much.

The fastest card (Ridata) shows 4.2 MB/s transfer rate. A modern hard disk (according to http://www6.tomshardware.com/storage/20 ... gb-04.html
will be at least 6 times as fast at 24 MB/s.

I know there are other commercial solid state hard drives, do they use better flash memory or something? I suppose that’s why they cost so much.

I've seen some use DRAM, and come with battery backup. Like http://www.mncurtis.com/curtis/curtispr ... irtoxe.htm.

[lenny]

Considering replacing hard drive by putting in 2 compact flash cards via a IDE to dual flash adapter, allowing card to be bootable and using them as master/ slave. This would allow me to have a totally quiet pc.
I only really use ms office (usually word) and explorer so I was thinking of putting windows on one card and office on another.

Maybe it'll be easier to get a motherboard and max out on RAM, then create a RAM disk and place your applications there. By Explorer do you mean Internet Explorer? Then you need to change the directories used for cache and cookies to the RAM drive.

I've come across RAMDiskXP but never tried it (never had the problem of too much RAM ). Link : http://www.cenatek.com/product_ramdisk.cfm

With enough RAM you should be disable the swap file. I'm not sure what to do about Windows DLLs though.

What will be really cool would be a way to boot up with hard disk, which will run the RAM disk, move everything there, then boot Windows from RAM disk, shutting down the hard disk. You get some noise on startup, then silence until you need to shut down (your registry, etc. will need to be written back to disk). You can also have a compact flash to store data files that you'd rather not lose. Virus? Spyware? Do a cold boot and you're back to the last good state. Does anyone know how to do this, or is it even possible?

[edcrane]

the ramdisk thing is cool, but it doesn't mix well with NT flavors (2k/xp/nt). I've tried it a multitude of times. On the other hand, it's relatively easy to setup a complete ramdisk in 9x. This is far more practical than the CF card setup. The only problem you might have with this scenario is getting the HD to powerdown immediately after you boot. The other thing is you'll certainly want a UPS to make sure you don't lose data. If this was my setup I'd just use a couple .bat files to automate the process of starting + shutting down.

[lenny]

The only problem you might have with this scenario is getting the HD to powerdown immediately after you boot.

Google returns a reference to a utility called hdsleep. I did not try it out though.

[ghowarth]

Thanks for the advice

Ghowarth- thanks for the links, I can’t get the minibox one to work though, how do the midget pcs use flash memory? Instead of a hard drive? How do they get around the ‘write counts' problem’?
I’m also not sure how fast it would be when connected to an ide connector
Looking at prices for cf cards I notice they are now selling 2gb cards, cost a fortune though

Thanks
jon

Sorry, that was www.mini-box.com. I think they just load up the OS (linux) from the CF card. I guess it is mainly used just for reading and not writing, as they only use a 32mb card for their basic model. Besides, a card this size costs about a tenner.

[pingu666]

www.dansdata.com he did/talked about this

[JON999]

Thanks for the advice again guys

Ducky- the microdrives seems interesting, are these really quiet? also would these not suffer from the 'limited writes' problem? maybe they won't if they are just really small hardrives? I read somewhere that some other companies are manufacturing microdrives apart from ibm/toshiba these are a lot cheaper as well, so I might be interested if they are really quiet

Lenny- yeah they are slower than hard drives, would this affect performance too much in word and explorer? or would 4mb per second write speed 5mb per second read spead be acceptable?
I also like the idea of using a ram drive, but without a harddrive I would need to leave the power on all the time so I wouldn't lose info, and they are not bootable I believe?
I like the idea of booting with flash and using ram for the swap file and everything else, then saving it back when I have finished or power down to get around the 'limited writes' problem. But I don't know if this is possible. Perhaps in future when flash is really cheap for big sizes someone will think of something or write some decent software that makes it work ok. Actually I'm sure they will as solid state is future I reckon.

Can get 1gb flash for £200 now anyone know if I could get windows, word and explorer on this amount?
Also this card uses wear levelling; Wear Leveling increases longevity by spreading the digital flash data writes across least used memory address sectors.
would the swap file or whatever still kill the card?
might be worth a try when prices go down, if it doesn't work and dies I could send card back and get another and use it for mp3 player or camera or something.

Thanks
Jon

[Ducky]

Thanks for the advice again guys
Ducky- the microdrives seems interesting, are these really quiet? also would these not suffer from the 'limited writes' problem? maybe they won't if they are just really small hardrives? I read somewhere that some other companies are manufacturing microdrives apart from ibm/toshiba these are a lot cheaper as well, so I might be interested if they are really quiet

Well, I've never actually used one before, but from what the people in this forum said, they seem to be pretty quiet. They don't suffer from the limited writes problem because they're literally an IDE hard drive made to look and act like a compactflash card. (Compactflash cards are, of course, flash memory made to act like IDE drives. So, if you use an IDE to compactflash adapter on a Microdrive, then you've come full circle.)

I like the idea of booting with flash and using ram for the swap file and everything else, then saving it back when I have finished or power down to get around the 'limited writes' problem. But I don't know if this is possible. Perhaps in future when flash is really cheap for big sizes someone will think of something or write some decent software that makes it work ok. Actually I'm sure they will as solid state is future I reckon.

Swap file is designed as something that gets written to when you run out of memory. Though Windows programs sometimes uses it as a temporary storage/synchronization thing...

As far as real flash card support, it's out there. It's just that the version of Windows with a flash card friendly filesystem is actually way more expensive than the retail version... (Look for Embedded Windows <whatever> for details. -- It's different from Windows CE)

Can get 1gb flash for £200 now anyone know if I could get windows, word and explorer on this amount?

Word and Explorer might fit in 1 GB, though I'm not sure. I'd wait a bit and buy the 4GB version that's due out soon, though. It's reportedly faster as well as higher capacity, and it might drive the 1GB cards down in price, as well.

Also this card uses wear levelling; Wear Leveling increases longevity by spreading the digital flash data writes across least used memory address sectors. would the swap file or whatever still kill the card?

Yes. The limit is still there, after all.

might be worth a try when prices go down, if it doesn't work and dies I could send card back and get another and use it for mp3 player or camera or something.

Over here in the U.S., one company (PNY) is even crazy enough to do a lifetime warranty on their compactflash cards. (Of course, they advertise it for digial cameras instead of as an IDE replacement, so I guess they don't expect people to 'kill' it very frequently...)

[fancontrol]

I use flash as the only drive on a mini win-98 box on a factory floor. It's been scanning barcodes and programming PROMs for two years without a failure.

Two things worth noting:

Even wimpy 98 freaks out when it only has 512 MB to work with. (Yes, I've thought about *nux and hope to get to it someday.)

Not all flash runs at the same speed. I have three different cards with mirrored data and they all have noticbly different response times. (Simpletech was the fastest. Individual results may vary.)

[JON999]

Thanks for the info fan control, I think I will give it a go soon. I just wanted to find out more before I spent the cash.

Concerning fitting the operating system on a flash card there is a utility called 98lite that cuts down win 98/me to a small size there is a free demo available as well; http://www.litepc.com I haven't used it yet, so if anyone does please let me know how they get on.

In this review of a VIA EPIA M-10000 1GHz Nehemiah Core board;
http://www.techseekers.net/modules.php? ... =60&page=3
the guy uses flash to replace the harddrive and manages to get win98 on a 128mb card ok.
I was thinking of disabling the hard drive and useing flash for word and office stuff and only enable the hard drive when I have too, or just getting rid of the hard drive completely, then my pc would be totally silent apart from dvd reading.

Jon

[Ducky]

I use flash as the only drive on a mini win-98 box on a factory floor. It's been scanning barcodes and programming PROMs for two years without a failure.

But is it storing the bar codes and PROMs on the flash drive and adding/deleting them fairly often? If so, then I guess I stand corrected on their longivity.

[scalar]

You can actually turn off the swapfile in Windows if your computer has a sufficient amount of memory. The problem is that most people are not willing blow a lot of cash on memory, so the swapfile takes up the slack.

Even for a boring office-job PC, 256 megs can be pretty tight, when you tack on anti-virus, instant-messengers, etc. (Since I play Anarchy Online regularly, even my 768 meg ain't enough to go without a swapfile. I've seen the allocated memory climb up to 1.4 gigs with AO and a few other programs running.)


Interestingly, if you have a lot of extra memory, Windows will automatically allocate it as a disk cache, which will speed up the opening of programs because the data stays resident in the RAM not allocated for use by running programs.


If you do decide to try this project, you will likely need to skip over a 512 meg card completely. The normal Windows 2000 setup cannot complete with less than a gig of disk space, because it copies a lot of setup crap to the target drive that gets deleted when setup completes.

In fact, I would not bother with trying to install Win 2000 from the setup CD. Instead, install Win 2000 on a spare hard drive, and you will have the freedom of extra disk space as you attempt to cut Win 2000 down to fit on the flash card. You can try turning off swap, or moving it to a second drive, or using a RAMdisk driver to create a RAMdrive for your swap (seriously!).

Then when you've got it working fairly well and the total volume size is under 1 gig, use Microsoft's SYSPREP utility to prepare the OS to be moved to another hard drive. Then use a disk imaging program like Norton Ghost to transfer it to the card. On first boot, Sysprep will reconfigure some system settings so that Win 2000 can run on the card.


One of the big chokepoints here is that Win 2000 needs a driver to read the card as it boots, or it will simply crash with a BSOD stop error. It is unclear whether Win 2000 will boot off the card even if the card appears in My Computer, as that may be a different type of device driver not used in the boot process. (If you don't have the correct disk device drivers installed for Win 2000, it is very possible in to see that white startup bar walk across the screen as if all is normal, and then suddenly it dies with a BSOD stop error.) I guess someone will just have to try it and see what happens.


Finally, as stupid as this sounds, Windows 2000 and Windows XP still rely on drive letters to find important system files. This means that if you installed Windows 2000 on drive C:, it will be extremely unhappy if you try to migrate it to a USB flash card that happens to believe itself to be drive F:. If this occurs, Windows will still boot, but it will be wholesale screwed up when the desktop appears, because it thinks all sorts of Windows DLL's are still sitting on drive C:. Device manager is non-functional, IE will not open, network is non-functional, etc etc.

Apparantly this can be fixed by scanning through the registry and changing all occurances of "C:\" to "F:\" but I have yet to find a utility that does this thoroughly and properly. Microsoft's REGFIND registry search-and-replace tool misses certain matches so that I can only repair Windows about 90% but not 100%.

[Ducky]

You can actually turn off the swapfile in Windows if your computer has a sufficient amount of memory. The problem is that most people are not willing blow a lot of cash on memory, so the swapfile takes up the slack.

Hmmm. Nope. There are a few programs that requires the use of a swapfile. (Win32 API's usual synchronization function stores the semaphores in the swap file.)

Interestingly, if you have a lot of extra memory, Windows will automatically allocate it as a disk cache, which will speed up the opening of programs because the data stays resident in the RAM not allocated for use by running programs.

Though this might potentially suggest that Win2K and up might be able to get away with it with enough memory.... (page file in memory?)

One of the big chokepoints here is that Win 2000 needs a driver to read the card as it boots, or it will simply crash with a BSOD stop error.

Finally, as stupid as this sounds, Windows 2000 and Windows XP still rely on drive letters to find important system files. This means that if you installed Windows 2000 on drive C:, it will be extremely unhappy if you try to migrate it to a USB flash card that happens to believe itself to be drive F:

CompactFlash, unlike its smaller counterparts, can actually be connected to the computer the same way as a normal hard drive -- all you need is a CF to parallel IDE adapter. Cost ranges from $16 to $30 online -- pinouts are actually the same IIRC, so you can build your own if you're so inclined. So, you can set the CF up as the secondary drive, copy the contents over, then switch it over to master and boot off of it. No problems.