AST Ascentia J Everything Site
Sorry, it isn't organized so well, I am slowly trying to compile information for the AST Ascentia J series laptops. A lot of people would consider this laptop obsolete. I consider it to be "just right" for my needs. With 40 MB of RAM (the max on this unit) it is plenty capable of running Window 9x, Linux, or FreeBSD. I mostly use Linux on the machine. Since I don't bog it down with unneccessary software like most Windows users do, the machine boots to the desktop faster than most people's 1,000 Mhz machines. I can play MP3s, MPEG videos, surf the web, and the lot. The fact that it doesn't have an internal CDROM is good news for people like me! It means it is worthless to average computer-illiterates because they would never be able to use it. That means the price is low so people like me can get them cheap and make good use of them!
Interesting Facts about the J series
- I believe the unit was assembled in Taiwan by Compal (but it might be Quanta, also in Taiwan). It was made for AST Computer and so far I cannot find this unit marketed under any other brand-name. If you know of one, PLEASE email me and let me know!
- It came with in five basic flavors: The J10, J20, J30, J50, & J55. The Processor speeds range, comming in 3 speeds: 75 Mhz, 100 Mhz, and 133 Mhz. CPU is on a daughtercard under the right palmrest and is interchangable. I upgraded my J30 (100 Mhz) with a 133 Mhz chip from a dead J55 and it works great!
- Four screens were available: 1) A Dual-scan passive-matrix color which could display 256 colors. 2) an Active Matrix color which could display 16-bit (65,535) colors. Also, there is a 10.1" and 11" version of both screens. All screens use 800x600 resolution. On the 11" version, the right speaker is gone and the wire which would normally go to that speaker is routed to the left and combined for a MONO sound. Screens on the Ascentia J are not interchangable. I have found you need the exact screen for the system. The best picture is given by the J30 with the 10.1" Active matrix. This screen is made by Samsung. All Ascentia Js will display 16-bit color on an external monitor. The display controller is the Chips&Technology 65548. It has been tested under Windows, Linux, and FreeBSD.
- The Ascentia J has a good reliability record. I used to work for AST and the most common problem was with the write-protect snesor on the floppy drive. If you stick a disk in at the just the right angle, it will bend or damage the detector and all disks will be considered "write-protected" by the drive. This isn't a big issue as I rarely use floppies and when I do I am reading from them. Also, the trackstick has occasionaly been known to be problematic. Also the PCMCIA door is known to break off easily. Other than these minor things, these are rock-solid laptops.
- You may have noticed when running on battery power the screen occasionally slowly changes brightness up and down. It seems to be normal, and slightly irritating. I found that if you just turn the brightness all the way down it never changes. Even with the brightness all the way down, the screen is plenty bright.
- Units came with 3 different modem modules. All are hard-ware controlled modems, fortunatly for Linux users. Modem speeds were 14.4K, 28.8K, and 33.6K. Modem modules are interchangable between different models. FYI: The 14.4K version has no MNP or V. anything error correction.
- For some weird reason IBM PCMCIA ethernet cards (also marketed under brand names of AST, and Thomas Conrad) do not work in the system. The PCMCIA controller thinks you remove the card a few seconds after it initializes it. Other cards seem to work great.
- Ever get a message about controlling the A20 line when rebooting? You need to always hard-boot when rebooting Windows 9x. This doesn't appear to be a problem with real operating sytems like Linux.
- Hear a lot of noise from the sound-card? Sorry, seems to be a design flaw. If you turn all the volumes down for all the mixer items you don't use (like Mix, Line, PC-Speaker, CDROM, etc..) it will help a lot, but it will always be there. It is there even udner Linux.
- Free-BSD users may encounter problems getting the sound card to work, also the IRQ taken by the sound card will keep PCMCIA ethernet cards from working unless you manually go into the PCMCIA setup and disable the use of IRQ 5 and/or 7.
- If you are trying to play MPEG movies fullscreen, all I can say is "sorry." There doesn't appear to be any hardware-stretch capability with the C&T 65548 chipset. At first I thought maybe the built-in windows drivers just didn't support it. I tried the ones from Intel (who bought C&T) but they actually cause problems with the display.. Not much hope under Linux with XFree86 either. update - I learned that the chipset does support hardware stretch but there isn't enough left over video RAM to use it. The framebuffer uses all 768K of video ram. If you lower the resolution to 640x480 and set it to 256 colors, some smaller videos are actually able to use it.
How to disassemble the unit
See pictures below of disassembly stages. First, there are 3 pieces of plastic to pop off. The hinge covers need to go first. They are on each side and you can pop them off with a flat tip screwdriver. They were designed to slide off to the left and right, respectivly.. so don't try to pry them "up" Once they are off, there is a long piece of plastic that is directly north of the keyboard and spans the complete horizontal length of the laptop. If you press down on the top row of keys, you'll see places to put a screwdriver in a pop it off. To get you started, look under the ESC and F3 keys. Once you pop all the joints, you can remove the plastic piece. Once it is off, the two screws holding down the keyboard will be obvious. Remove them and the keyboard comes off.
How to remove/change the screen
Once the two screen hinge covers are off (see above) you'll see that there are two screws on each side that connect the frame of the screen to the frame of the notebook. You will want to actually close the screen before trying to unscrew these. The wires that carry the video signal, power for the backlight, and speakers are routed from the motherboard through the centerpiece which has the battery status and other symbols. This part is tricky, once you've unplugged all the white connectors from the motherboard, you'll need to carefully pry these cables out from where they are wedged. If you want to take the screen apart, there are two screws on the front of the screen towards the bottom. One is near the power button. They are covered by rubber pieces. Use a knife or other sharp object to pry the rubber pieces off, to reveal the screws. To remove the bezel requires wedging something in between the two plastic panels and popping it apart, a pocket knife works well. Try to use the knife in parrallel to the plastic pieces, not perpendicular.
How to get to the motherboard and CPU
The plastic bezel which contains the palm-rest is somewhat a trick to remove. Be sure to take off all necessary screws, dont' forget the ones in the battery compartment. Don't forget to disconnect the little cable that goes to the battery-status screen. Once all the screws are out, the palmrest is still connected via some snaps at the front edge of the laptop. There isn't much I've found you can do other than just work it loose and it will eventually snap off. After that all that is really left is to get the heatsink removed. It is easy enough and if you are wanting to upgrade or change out the CPU, this is as far as you need to go. You can also get to the modem from here too.
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