Micro A1-C, overclocking, PCI cards

A forum for AmigaOne XE and MicroA1-C specific issues.
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sailorMH
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Joined: Wed Aug 28, 2013 6:01 pm
Location: Czech republic

Micro A1-C, overclocking, PCI cards

Post by sailorMH »

Hello to all! I have new pet from last year - Micro A1-C.
And I have some info and questions for A1-C users.
My A1-C has CPU 750FX v2.2 and U-boot 1.2.0.


1. In Intuition base Unofficial uA1-C Handbook there is a minor error on article 4.12 Adjusting the CPU Core Voltage (VCC_CORE(V) ):
On second data line (1.39V) is written 3-4pin=CLOSED. Correct value is 3-4pin=OPEN. (CLOSED here means voltage 1.49V).
I succesfully overclocked my A1-C to 933MHz with voltage 1.39V. With not-original cooler it is cool, stable and faster (was 800MHz).
This is great, because my 750FX have official limit 900MHz, and even voltage 1.39V is lower than nominal for this CPU type = 1.45V +/- 0.05.
Can somebody overclocked 750FX to 1000 or more? Even if I have good cooler and open testbed, I don't want to test it now.

2. I tried many graphic cards (PCI, AGP, PCI-e) in PCI slot, because onboard Radeon 7500 have only 32MB, which is big limitation.
No success. It seems to be normal, I didn't find any succesful external graphics use on Amiga forums.

3. Use of SATA controllers.
I tested two types SiI3114 and SiI3512.
SiI3114: is OK with U-Boot, I can boot from it, but after kickstart load and execution of exec, there are r/w error on SSD, even with PIO mode. ( Note: the same SSD connected to a1ide works fine)
SiI3512: not works with U-boot, it is visible here, but not possible boot from it, but after kickstart loading it works like a charm, with UDMA 133MB/s.
So my actual disc configuration is:
- a1ide.device:0 cfcard (with IDE-CF reduction), DOS7/FFS partition with /kickstart directory (identical copy from SYS:)
- a1ide.device:1 SATA DVD (with Axago IDE-SATA reduction)
- Sil3512ide.device:0 SATA SSD with SFS2 partitions, System: and Work:
This configuration works great, but I have here one question:
If I set with mediatoolbox a1ide.device:0 cfcard format fo SFS2, after boot disk under AmigaOS is unreadable, and cannot be formatted. But if I set it to DOS7, everything is OK.
My 32GB CFcard used on Pegasos have SFS format with no problem. Maybe this second CF card is too slow? It is my spare, very old, slow and 4GB size.

4. USB2.0. I tested four USB2.0 cards, with NEC chips, all of them works in Sam440ep-flex ans Pegasos2 under AmigaOS4.1fe like USB 2.0, but hangs with A1-C. I searched this forum - here are mentioned some USB2.0 cards working at least in AmigaOne XE, but I cannot find any which works in A1-C with USB2.0 speed.
Please, can somebody have functional USB2.0 inside A1-C? And which exact type please?

5. Did somebody succesfuly test 1Gbe NIC in A1-C? I think only Realtek RTL8169/8110 is compatible. The one borrowed from my X1000 didn't work. And I wonder if there is some net speed increase or not.


Thank you. I will be grateful for any comments or advices.
Micro A1-C (G3/1.2 GHz), AmigaOne XE (G4/1.4 GHz), Pegasos II (G4/1.33 GHz), Sam440ep, Sam440ep-flex, AmigaOne X1000
Efika 5200b, Pegasos I, Powerbook, Mac Mini (1.83 GHz), iMac, Powermac Quad

AmigaOS, MorphOS, linux, MacOS X
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