To be quite honest, I think the IDE interface is likely to be bottleneck when it comes to using a CF card as HD for a DOS based system.

The access time of a CF card is certainly nice but not all of them are particularly fast and most (if not all) have terrible write performance with small files. The write performance can make them unbearable in some cases because it will make the system stutter/pause.

For DOS it shouldn't matter.

I tried cheap ones from eBay and branded ones and also micro drives. All work fine.

However I have no settled for a PCI SATA controller card and standard 2.5" notebook drives. I created a 30GB FAT32 partition.

I've settled for PCI SATA controllers and first generation 32GB SSD drives. Overkill you say?

Just on principle I don't use the built in hard drive interfaces on any of my really old machines. I always use an interface card that supports a faster and/or newer specification. The old interfaces are just too slow and take up too many CPU cycles. The drive capacity is also lower when you use them. I'd rather be able to use newer, faster, higher capacity drives.

It doesn't matter how fast the CF card is above 266x as the adapters for some reason will cap at udma 33 speeds however it is best to search out the rare few cf cards that are SLC. The other method is a bootable pci raid card with sata. IDE can handle on some boards over 90mb/s if the controller supports the ata133 standard but most of the p3 era will be capped at udma 66 and most ss7 will be at udma 33 with a handful supporting the 66. As for a 486 you might be using a pci card anyway instead of the isa/vlb era controllers that would barely sustain a 133x cf card.

LunarG wrote:

To be quite honest, I think the IDE interface is likely to be bottleneck when it comes to using a CF card as HD for a DOS based system.

Depends on which card you are using. A common 133x CF will have theoretical rates of 21,5 MB/s (in reality probably less), while a UDMA33 interface can theoretically provide 33 MB/s.

swaaye wrote:

The write performance can make them unbearable in some cases because it will make the system stutter/pause.

Irrelevant once you load your system up with enough RAM.

sliderider wrote:

Just on principle I don't use the built in hard drive interfaces on any of my really old machines. I always use an interface card that supports a faster and/or newer specification. The old interfaces are just too slow and take up too many CPU cycles. The drive capacity is also lower when you use them. I'd rather be able to use newer, faster, higher capacity drives.

That will hog the PCI bus though...

d1stortion wrote:

LunarG wrote:

To be quite honest, I think the IDE interface is likely to be bottleneck when it comes to using a CF card as HD for a DOS based system.

Depends on which card you are using. A common 133x CF will have theoretical rates of 21,5 MB/s (in reality probably less), while a UDMA33 interface can theoretically provide 33 MB/s.

When I was referring to DOS based systems, I was primarily thinking of up to P1 level systems, which means you're much more likely to be running PIO modes rather than UDMA. In which case, the interface is likely to be the bottleneck. And even with UDMA33, theoretical transfer rate and real-world transfer rates are often quite different. I agree, that for a high performance P2 or higher, the interface may not be the limiting factor, but in old world DOS, it likely will be.

Yeah a DOS system may be fine with poor write speeds anyway. You can't really multitask so there's not going to be much impairment to system use during writes after all.

Read performance isn't really a concern. Almost any recent CF card should move data faster than the hard disks of the old days, and the instant access time is nice.

Even for Win9x gaming performance CF cards mostly cut it. Save for those few games that won't start up with disabled swap file. I don't see the need for heavy multitasking as that's certainly not what I have such a PC for in the first place.

You're far more likely to run into problems with games that continuously load their data from the CD. Even a puny cheap CF with a virtual drive is going to be a lot faster in this case.

The cause of problems with CDROMs is their extremely long access time and tendency to be unreliable junk. A CF card certainly solves those problems.

chinny22 wrote:

I've got a question about Fixed disk CF cards if anyone can help […]
Show full quote

I've got a question about Fixed disk CF cards if anyone can help

After messing around for a day I have learnt much but sadly don't think I can use this card for this setup.
Trying to set this up on my Dos 6.22 486, BIOS detects the correct size but using the updated Win98 fdisk I cant create logical drives over a couple hundred MB where my 10GB HDD would partition fine (Taking in account the 8GB limit)

I tried to partition it with gparted and can make the logical drives fine and show correctly in WinXP but Dos can only see the primary partition. Fdisk can see the extended but no logical drives.
I'm pretty sure this is because it is still not in fixed disk mode but using ATCFWCHG.com just gives errors.

My experiences, albeit with a 'true' CF II "microdrive" (no alignment* or wear level issues), is that you have to use REAL DOS 6.xx(not the win98 floppy) to perform all the disk editing.
If you want to install older DOS on it, that is.

- FDISK for the partitions
- then FORMAT them
- and SYS C: etc
from a bootable DOS 6.xx(or even 5?) CD or floppy...

Had much trouble with trying to create/format more than 1 working partition if using anything else. Not sure how it relates to your particular problem, but worth a shot ?

*: Compact Flash as hard drive - formatting and partioning.
http://www.ebay.com/itm/370661454126

Some other links:
http://www.pscience5.net/CFPartition.htm
http://eab.abime.net/support-other/68350-pc-a … ne-cf-card.html
http://www.thinkwiki.org/wiki/CompactFlash_boot_drive

Yes I do the same. For DOS 6.22 you can get bootdisks from bootdisk.com.

For FAT32 I use a BootCD with Super FDISK as the Microsoft tools can't deal with hard drives that are too large.

I highly recommend sticking to a 30GB FAT32 partition as the max.

Now under DOS 6.22 you can create several 2GB partitions (e.g. four 2GB partitions). They will however NOT show up under Windows (with a USB CF card reader), only the first one, however LINUX will show all four partitions.

PCI SATA card is not an option due to the 1st 3 letters PCI, VLB or SCSI is an option but I'm back to using old drives again.
Besides I like working to the motherboard limits, for better or worse. After the CPU its what defines the PC who she is.

Bestemor, yes tried dos fdisk, in fact I still my preferred choose over the WinNT and above setup flavour of partition software
This time however fdisk couldn't create extended permissions.

Mau1wurf, that's exactly what I'm trying to do and the results (can only see the first 2GB partition) I was under the assumption this was because it was being detected as a removable disk, or have I missed something else?

On a side note, I had a quick play with the 2GB I can see, Doom and Duke3d I didn't see much of a difference from the HDD, maybe bit quicker but not a big difference.
I forgot the swap file for Win 3.11 was on D:\ so was surprised/annoyed to see it there but it does load much quicker

The only reason why some CF cards are so bad when it comes to dos and win 9x is due to the very poor random 4k on some cards, second you need at least an 4gb card due to performance reasons. The best bang for buck CF cards are the slc models and they can easily handle much higher workloads including osx and even win 7 when used right.

CF card or go back to mechanical.

chinny22 wrote:

Mau1wurf, that's exactly what I'm trying to do and the results (can only see the first 2GB partition) I was under the assumption this was because it was being detected as a removable disk, or have I missed something else?

No it's a "feature / limitation" of windows. Nothing more nothing less.

Under Linux > All partitions show up with a drive letter mapped to each partition.

Not sure about OSX, worth a try if you have a Mac at home!

This is the MAIN reason I switched to FAT32...

Why use a HDD that is faster than the 486's internal ram speed.
If the ram runs 40mb/s in typical speed, the hdd or cf speed would be half of that or lower i think.

I use a 4GB dom that handles only 6mb/s in dos, and a 5gb quantum hdd for windows, just because win like to write to several same sectors every several seconds and flash based cards ware out on the sector writes.

I always use hdd's, get two of the same type, most time the electronics will die first, then you can swap the controller over from a good drive to the bad and save tha data.
Plus you get to benefit to listen to the hdd seek sounds, which i miss on modern machines, only the spindle rotation speed is a little annoying to hear but we have also fluid bearing drives so solved.

Tried a USB stick with Mac OS 10.6.8 and it could see all 3 partitions. Not that I care, still don't like Apple, sorry.
I've managed to get a Fixed disk CF card through work supplier for a bit extra then a standard card (If anyone asks my 486 is a POS terminal)
Sadly its a 1 off discount as is for trial purpose.

Hey has anyone here managed to wear out a CF card? Supposedly they do wear leveling but I am suspicious about it. I assume wear failure would manifest as bad sectors.