SupraDrive 500XP slow?

[Ral-Clan]

Hi, Sysinfo shows that my SupraDrive 500XP gets 638,856Kb / sec.  This seems a little on the slow side to me.  I've never really used this hardware before (only an A2091 in an A2000 before).  Does this seem okay to you guys?

I realise the SupraDrive controller card only does PIO mode transfers, but a half-meg a second still seems slow.

[Ral-Clan]

Okay, can anyone recommend a reliable tool for measuring SCSI hard drive transfer rates?

EDIT: Ahhh. I see...."RawSpeed".

Thanks.

[Ral-Clan]

Well, RAWSpeed shows about the same results as SysInfo 4 does.....about 650,000 Kbytes per second.

That seems pretty bad.

I also tried the other SCSI Speed test linked to in that other threat and got the same results.

The other weird thing is that CPU availability goes down to about 0% to 2% during SCSI activity.  That really seems wrong.

I have an Amiga 500 with 2MB Chip RAM (Megachip + Fatter Agnus), 2MB Fast RAM (on the Supra500XP) OS3.1.

The drive is a 2.1GB Quantum.  Maybe it needs termination or some jumper change.

[Ral-Clan]

Mine is a standard, unaccelerated A500+.  I do have the 68010 processor in mine, but that really doesn't make any difference.  Try boosting your fast ram.  If that doesn't work, it is still better to have more fast ram. Like I said, I only got about 1 megabyte/sec on my spare A500+8, which has only 4 mb of fast ram.  I get 2 megabytes/second from the one with 8mb of fast ram.

Interesting that there's such a difference considering they are very similar products (A590 and Supra500XP).  Maybe I will go up to 8MB RAM with this.

I don't know if that the extra fast ram is the reason, for sure, though. Are there any chips in the Supra, that might have a later version.

Yeah, I have the latest ROM chip - AMAB6.

Do you know how much CPU usage your A590 takes during transfers?

[Ral-Clan]

Test with this speed measuring tool and please let me know what it says for CPU.

http://aminet.net/package/util/moni/RSCP

[Ral-Clan]

I used to have one years ago.  It has no RAM expansion (without finding the special add-on card).  It's also PIO.

Supra500XP is a good sidecar (RAM + SCSI).  It's just a little slow - not unbearably so - heck I would hardly notice if I wasn't seeing the better specs on the other sidecards mentioned above.

[Ral-Clan]

I have a SupraRAM card, and from the ones I've had, it is my favorite RAM expansion.  But, I do like the GVP cards.  I've never had any experience with the Supra SCSI cards.  I will run the CPU test, and get back with you.

Okay, thanks.  I am interested to see the results.

[Ral-Clan]

OK, so I ran the test on my A500+.  Here are the results:

read speed:  2.178 MegaBytes/Sec.
Busy/Idle Percentage:  70%

Wow!  You are getting really, really good transfer rates (quadruple my Supra 500XP).

I guess the A590 is just better than the Supra500XP.  That's strange, because I thought both used PIO (Programmmed I/O) transfer modes, which are known to be fairly slow.

You are also getting pretty good CPU performance (low load on CPU).

By the way, how is that Chinese RGB->VGA converter you are using?  Is it as good as a flicker fixer (i.e. Indvision?) or is there some blurriness added?

[Ral-Clan]

I wonder if my mask / maxtransfer settings could be wrong?

Mine are set to MASK 0xfffffe, Maxtransfer 0xffffff

Do you know what yours are set to?

If it's not these settings then I'll just accept this is a slower piece of equipment by design.

As for the scan-doubler thing - I'm glad you're happy with it.  I'd mostly be using it for non-games, too: i.e. DPaint - where sharpness is pretty important.

I read on another thread that you like it, even though you consider yourself pretty picky.  But on other threads people have been saying it's terrible.  What contradictory information I'm finding.  I guess the only way for me to tell for sure would be to find a high-res screen capture or video of it in use on an amiga somewhere online.

I found this video:
http://www.youtube.com/watch?v=wBvJcQj44tw

and it looks rather GOOD!  (i.e. text is sharp enough) ---- but the guy won't hold the damn camera still enough.  None of the videos of Amigas using this device on YouTube are good enough quality to judge (either shakey cam or low resolution cameraphone).

[Ral-Clan]

what file system are you using?  Is it FFS, SFS, or PFS?

It's just the standard FFS.

But reading the specs of your sidecar vs. mine --- I'm guessing yours can do DMA accesses which the Supra cannot.  I'm guessing that's why yours is so much faster and less draining on the CPU.

Also, the design of the GVP is so nice in that it matches the A500. Why Commodore could not do as nice a job I often wonder.