I would like to speed up my 486 PC by replacing my IDE PIO 4 HDD (max transfer rate of 16,6 MB/s) with a much faster one. So I am considering to install a PCI controller card to take advantage of the PCI bus max transfer rate of 133 MB/s.
I am hesitating between PATA 133, SATA 150 and SCSI U160 types of controller cards. What advantages does each type have over the others in this case? What would you recommend?
With a lot of the pata pci controllers you simply won't be able to boot from them in 486. Best chances you would probably have would be with a SCSI card with a bootrom and it would be nice if the bios has boot from scsi option.
UDMA vs PIO is a lot bigger jump than the versions between them. Jumping from PIO to UDMA frees up huge amount of CPU time. (and you want that on 486!)
What operating system are you using? In dos you can search for UHDD & UDVD2 drivers, that support DMA operating modes. In windows 95+, you can tick "DMA" checkbox on the harddrive in device manager, if you have proper (and supporting) IDE controller drivers installed. (Might be difficult to aquire)
"640K ought to be enough for anybody." - And i intend to get every last bit out of it even after loading every damn driver!
wrote:UDMA vs PIO is a lot bigger jump than the versions between them. Jumping from PIO to UDMA frees up huge amount of CPU time. (and you want that on 486!)
What operating system are you using? In dos you can search for UHDD & UDVD2 drivers, that support DMA operating modes. In windows 95+, you can tick "DMA" checkbox on the harddrive in device manager, if you have proper (and supporting) IDE controller drivers installed. (Might be difficult to aquire)
Dual-Boot, MS-DOS 6.22 and Windows 98 SE.
I don't think that my onboard IDE controller (ALi M1489) has support for UDMA.
ALI1487 / 1489 dma support win95 + dos udma enabler
Here's someone with similar board, found drivers and enabled MWDMA. (At glance, similar benefits with UDMA)
Hope it helps you too. 😀
"640K ought to be enough for anybody." - And i intend to get every last bit out of it even after loading every damn driver!
wrote:With a lot of the pata pci controllers you simply won't be able to boot from them in 486. Best chances you would probably have would be with a SCSI card with a bootrom and it would be nice if the bios has boot from scsi option.
Actually I don't know if it could boot from a drive connected to a PCI controller card... I have extracted the possible related entries from the BIOS (AMIBIOS 1994):
Standard Setup:
- Master Disk: Not installed, 1-46 different HDD types, user defined (type 47), ESDI, SCSI.
- Slave Disk: Not installed, 1-46 different HDD types, user defined (type 47), ESDI, SCSI.
Advanced Setup:
- System Boot Up Sequence: A: C:, C: A:
- Secondary IDE Drives Preset: None, 1, 2.
- IDE Block Mode: Auto, Optimal.
- Primary IDE 32-Bit Transfer: Enabled, Disabled.
- Primary 1st IDE Block Mode: Enabled, Disabled.
- Primary 1st IDE LBA Mode: Enabled, Disabled.
- Primary 2nd IDE Block Mode: Enabled, Disabled.
- Primary 2nd IDE LBA Mode: Enabled, Disabled.
- Secondary IDE 32-Bit Transfer: Enabled, Disabled.
- Secondary 1st IDE Block Mode: Enabled, Disabled.
- Secondary 1st IDE LBA Mode: Enabled, Disabled.
- Secondary 2nd IDE Block Mode: Enabled, Disabled.
- Secondary 2nd IDE LBA Mode: Enabled, Disabled.
Chipset Setup:
- PCI IDE Card Present in: Auto, ISA, PCI Slot 1, PCI Slot 2, PCI Slot 3.
- PCI IDE Trigger Type: Edge, Level.
- Primary IDE IRQ Connected to: INTA, INTB, INTC, INTD.
- Secondary IDE IRQ Connected to: INTA, INTB, INTC, INTD.
Peripheral Setup:
- Onchip IDE: Enabled, Disabled.
- Onchip IDE Secondary Port: Enabled, Disabled.
- Onchip IDE Mode: Auto, Mode 0, Mode 1, Mode 2, Mode 3.
I'd recommend against SCSI, drives are noisy, old and only going to get harder and more expensive to replace.
SATA is obviously the best as its the complete opposite of the above, dont know of any cards to recommend though.
IDE you may be better off with a CF/SD card with its faster seek times on the existing controller then trying to get bit more performance out of spinning disks and PCI overheads
Maybe what you're looking for is a Pentium? 😉
In all seriousness, what performance issues are you specifically trying to cure? The only time I've noticed disk I/O to be a bottleneck in DOS is during installs or copying data from one place to another. DOS and "performance" aren't usually used in the same sentence, except when highlighting the benefits of ... pretty much any other OS. It is optimized for minimal use of memory, constantly consults the FAT tables and directory entries, has barely any caching (so you're constantly waiting on the disk heads to seek), the block sizes are minuscule, etc...
On top of that, 486-era disks are just slow, even with fast(er) controllers. Luckily, there just isn't that much that needs to be I/O'd. Think about it this way: You could copy an entire Win95 installation across a PCI bus in about two seconds. With your 16MB/s current limit, it would take around 15 seconds. If it's taking a substantial amount of time to do what you want to do, maybe raw throughput is not the source of the problem?
Different story with Win98, though I seriously question the sanity of anyone trying to shoe-horn Win98 onto a 486. 😁 The disk probably shouldn't be your primary concern in this case.
All this to say -- are you sure this is where you need to optimize? If you just want to because hey why not, then... more power to you. We're all a little nuts around here. 😀
wrote:I'd recommend against SCSI, drives are noisy, old and only going to get harder and more expensive to replace.
SATA is obviously the best as its the complete opposite of the above, dont know of any cards to recommend though.
IDE you may be better off with a CF/SD card with its faster seek times on the existing controller then trying to get bit more performance out of spinning disks and PCI overheads
The easiest going forward will be an IDE-SATA adapter, mechanical drive, and LBA limits on the drive via SeaTools. Even if you have a 500G drive and you can only use 8.4G of it, they're so cheap to begin with software was so much more compact then. Plus, seek times are low enough on modern mech drives that you'll feel your computer is rocket propelled.
All hail the Great Capacitor Brand Finder
wrote:The easiest going forward will be an IDE-SATA adapter, mechanical drive, and LBA limits on the drive via SeaTools. Even if you have a 500G drive and you can only use 8.4G of it, they're so cheap to begin with software was so much more compact then. Plus, seek times are low enough on modern mech drives that you'll feel your computer is rocket propelled.
Agreed, if it was me I'd go with CF/SD first then adapter. Wouldn't bother with controller cards as all
Forgot to mention issues with the removable flag. CF and SD is fine for DOS, but you can run into problems with some versions of Windows.
All hail the Great Capacitor Brand Finder
wrote:ALI1487 / 1489 dma support win95 + dos udma enabler
Here's someone with similar board, found drivers and enabled MWDMA. (At glance, similar benefits with UDMA)
Hope it helps you too. 😀
I've followed your advice and I've installed the proper driver but I am not so sure about the benefits. I've posted my results in the quoted thread: ALI1487 / 1489 dma support win95 + dos udma enabler
wrote:Maybe what you're looking for is a Pentium? 😉
I don't have to look for a Pentium because I already have one (IBM PC 350). 😉
wrote:In all seriousness, what performance issues are you specifically trying to cure? The only time I've noticed disk I/O to be a bo […]
In all seriousness, what performance issues are you specifically trying to cure? The only time I've noticed disk I/O to be a bottleneck in DOS is during installs or copying data from one place to another. DOS and "performance" aren't usually used in the same sentence, except when highlighting the benefits of ... pretty much any other OS. It is optimized for minimal use of memory, constantly consults the FAT tables and directory entries, has barely any caching (so you're constantly waiting on the disk heads to seek), the block sizes are minuscule, etc...
On top of that, 486-era disks are just slow, even with fast(er) controllers. Luckily, there just isn't that much that needs to be I/O'd. Think about it this way: You could copy an entire Win95 installation across a PCI bus in about two seconds. With your 16MB/s current limit, it would take around 15 seconds. If it's taking a substantial amount of time to do what you want to do, maybe raw throughput is not the source of the problem?
Different story with Win98, though I seriously question the sanity of anyone trying to shoe-horn Win98 onto a 486. 😁 The disk probably shouldn't be your primary concern in this case.
All this to say -- are you sure this is where you need to optimize? If you just want to because hey why not, then... more power to you. We're all a little nuts around here. 😀
I just want to make this 486 as fast and up-to-date as possible, just for fun. Overclocked AMD 5x86-P75 (4 x 40 = 160 MHz), 512 KB cache, 64 MB RAM, USB PCI Card... I am not worried about DOS performance but Windows one. It is a bit laggy while opening folders. Maybe a higher raw throughput along with a modern hard disk would speed up it all. "Why not" is my motto. 😀
Hi there, nice plans you've got going.
Personally I remember having (Got it working though) quite a few troubles having both a scsi and sata card in my 486. I found SCSI was easier to work with in my case for booting from.
I ended up just moving to a 2/4GB Ultra II Sandisk card that supported udma and configured my other drives for storing other stuff on that was needed. So 2/4GB CF Card and Scsi drive was around 8GB from memory.
Quite a few promise based cards have BIOS on them, but I could never get my 486 to boot without using 3rd party tools (which defeated the purpose for me)
SCSI Does tend to be a little noisy as well, but it worked around the built in bios limitations 😀
For mechanical reliability - SATA = def way to go with a budget drive maybe even in a pull out caddy or something.
Big issue is PCI / 486 saturation..... But you'll max it out for sure 😀
I have 2x 256gb Sata SSD on my P150 W98 !!!!!! Way overkill!
Love to see pics of build, good luck 😁
