VOGONS


Reply 21 of 344, by melbar

User metadata
Rank Oldbie
Rank
Oldbie

No, you cannot compare these two boards: Abit KT7(A) and Abit KG7

They have chipset which come from different "Socket A - era"

Release:
KT133 - Aug 2000 - 100Mhz (200MHz DDR) FSB, and SD-Ram
KT133A - June 2001 - 133Mhz (266MHz DDR) FSB, and SD-Ram
KT400 - Aug 2002 - 166Mhz (333MHz DDR) FSB, and DDR-Ram

#1 K6-2/500, #2 Athlon1200, #3 Celeron1000A, #4 A64-3700, #5 P4HT-3200, #6 P4-2800, #7 Am486DX2-66

Reply 22 of 344, by cde

User metadata
Rank Member
Rank
Member

Are there motherboards with SSE2 capable CPUs and at least one (DMA capable) ISA slot?

EDIT: to answer my own question, there are some rare P4 motherboard that might have an ISA slot. This thread has more information: Pentium 4 with ISA . Also see https://flaterco.com/kb/plague/index.html and https://flaterco.com/kb/ISA_chipsets.html

A possible alternative would have been SB-Link but it seems it disappeared together not long after ISA. 😐

Last edited by cde on 2019-10-09, 13:08. Edited 3 times in total.

Reply 23 of 344, by cde

User metadata
Rank Member
Rank
Member
FFXIhealer wrote:

If it were me, choosing to trash a board or spend money to fix it depends on the perceived value of the product to you. Since this is entirely subjective, no one here can give you a recommendation. But I can tell you that I was ok with paying to recap my motherboard because it was the 2nd computer I ever bought and I gamed pretty hard on it back in the day, so there are memories there.

Thanks for the advice. I have bought two KT7 capacitor caps from Chris @ badcaps.net and tried to repair the KT7A 1.3 motherboard which as I mentioned could barely boot (presumably due to bad capacitors). Indeed after visual inspection I found three bulging capacitors, which I replaced successfully but that was a lot of hassle, especially the two sitting between the AGP and PCI slots (the third one is above the number 57, changing it was not difficult):

wAYLPNy.jpg

I failed to properly remove the solder for the two aforementioned caps, so the top one has legs that do not go all the way through, and as you can see I found a workaround for the bottom one. Fortunately during the recapping I did not mess up any trace. My mistake was to not try to exercise recapping on a trash motherboard.

By the way, using a multimeter that can measure capacitors I did in fact confirm that the three I removed were bad. Unfortunately it is difficult to assert whether other capacitors are bad without removing them because the circuit they're connected to alters the measurement.

After recapping the segfault issue disappeared which is great! 😀

However the other two issues I had remain:

  • * DRAM slot 1 remains bad
    * if I try to change something in the BIOS, the PC won't POST. I have to clear the CMOS by unplugging the PSU and setting the jumper for a few seconds. Then the PC will POST, and I can change BIOS settings just this time (after that, any attempt to change BIOS settings will cause the issue to occur). Has anyone one this forum had this problem? (note I have already replaced the BIOS EEPROM chip itself, as well as the 3V battery)

Reply 24 of 344, by cde

User metadata
Rank Member
Rank
Member

So legacycollector.org is no longer available (apparently the maintainer received threats). Anyhow I'm posting here the latest versions of uBlock and noscript that work with older versions of Firefox, so that it may be useful to other people. In addition I've updated the first post with new information from my experiments, notably the use of an mSATA SSD drive.

Attachments

Last edited by cde on 2021-03-04, 07:27. Edited 1 time in total.

Reply 25 of 344, by cde

User metadata
Rank Member
Rank
Member

A SDRAM stick decided to give up and while doing so caused a shortcut in a small SOIC component below the RAM sockets, which gave smoke and the package is now bumped. Looking at it I read: HC26 FD8 (or FDS) 8958A. The FDS8959A is a "Dual N & P-Channel PowerTrench MOSFET" that can work at up to 30V at the drain so I'm unsure if that's the component that's really used on a motherboard. It's from 2010 and used for LCD inverters.

On two other KT7A I can read "4562 AA W0BB" and "4562 AB T11B" and "4562 AD W006". Can't really find anything about those components online 🙁 Does anyone have any idea?

EDIT: after further testing on a working motherboard, this component is I believe the FDS8959A. pin 1 and 3 (source S1 & S2) are at 3.3V while pin 2 and 4 (gate G1 & G2) are at 7.5 volt. The output (pins 4 to 8 ) are tied together and provide 3.3V to the SDRAM's Vdd. This is a pretty weird choice from from Abit, for example the QDI KinetiZ 7E, a very similar motherboard, has a standard 3.3V LDO regulator.

Reply 27 of 344, by shamino

User metadata
Rank l33t
Rank
l33t
cde wrote on 2020-12-06, 21:35:

Just to report that the replacement of the FDS8959A was successful! This KT7A is back to working again 😀

Thanks for the info on that repair. You never know when somebody else might run into the same thing. 😀

I have an "unrestored" KT7A that I bought a couple years ago that I need to recap and try out sometime. It's an appealing option for a high powered Win98/DOS machine.

Reply 28 of 344, by cde

User metadata
Rank Member
Rank
Member

Thanks shamino, it is indeed a great option. Now I'd like to report on my (mis)adventures with two similar boards, the QDI KinetiZ 7E (KT133A based) and QDI KinetiZ 7B (KT133 based).

The first issue is apparent when installing the CPU cooler, contrary to the Abit KT7A socket which as a north to south orientation, the QDI KinetiZ 7E/7B have a right to left orientation, with capacitors blocking even regular sized coolers. The problem is slightly worse with the 7B but also present with the 7E. So I resorted to desoldering a capacitor and soldering a new one lying on the side to make room (see picture attached for the 7B).

A second issue is that only the latest BIOS (4.1 LCP) supports LBA mode. However it does not support LBA 48 (48-bit sector size), only LBA28. When a disk larger than 128 GB is used (eg. a 250 GB SSD), the BIOS mistakenly falls back to LRG (large heads) mode and the operating systems cannot boot if any boot driver lies beyond the classic 33.8 GB (65535*16*63*512) barrier (cf. https://www.win.tue.nl/~aeb/linux/Large-Disk-4.html ). Another problem is that this incorrect LRG mode confuses Windows 98's built-in IDE driver, as well as VIA's 4in1 IDE driver. Both refuse to load and Windows falls back to compatibility mode. The solution for this issue was to use a 128 GB drive, in which case the BIOS enables LBA mode correctly and IDE on Windows 98 works without issues. Note that the latest BIOS on the KT7A support LBA48.

Another issue is the general lack of clocking/revolting options in the BIOS. The multiplier must be set manually with jumpers in accordance to the manual, with 12 being the highest. A CPU with unlocked multiplier is required, such as an Athlon XP mobile or Athlon XP before week 38 of 2003 (I tried an Athlon XP manufactured after this data and the system wouldn't boot). The maximum CPU frequency on the QDI KinetiZ 7E is 1600 MHz (133*12) and on the KinetiZ 7B 1200 MHz (100*12). The 7B in theory supports a 133 MHz FSB with a jumper but the system wouldn't boot even though the same CPU worked fine with FSB at 133 MHz on the 7E. (I don't think the KT133 supports a 133 MHz FSB anyway?)

Voltage cannot be adjusted, for example an Athlon XP mobile gets 1.58v which is fairly higher that the 1.45v the AXMH2200FQQ3C requires and leads to higher energy consumption, putting more stress on the board and the PSU. This is a bit drawback coming from the Abit KT7A which would allow undervolting the CPU down to 1.2v.

Both the 7B and 7E have no issues with running SDRAM at 133 MHz (it must be enabled in the BIOS though). However running memtest86 I'm seeing errors when accessing memory above 512 MB. This is an issue that is also seen on KT7A boards (but not always, seems to depend on the revision. I've had more luck with 1.0 boards).

The GOTEK floppy I am using was flashed with HxC and there were constant bit errors when accessing floppies, DOS install would fail at the first files being copied. This must be a software incompatibility between the HxC emulator and the QDI KinetiZ hardware since the KT7A has no such issue. A workaround I found was to use FlashFloppy instead of HxC, the bit errors disappears and the installation of DOS / Windows 3.1 worked without fail.

Both the 7B and 7E have a useless AMR port. Furthermore, on the Abit KT7A I could run a GeForce 4 and Voodoo 3 PCI in tandem, using the Voodoo on DOS/Win98 and the GeForce on XP/Linux, but the same configuration on the 7E is much less stable (even though I recapped it). So I'm now only using a Voodoo 3 AGP plus some active cooling with the 7E, it is so far stable. I discovered by the way that Windows 3.1 has drivers for the Voodoo 3 which is nice. The VBEHZ utility is also super useful although the modelines must be tweaked a bit for my CRT.

Overall I wouldn't recommend the QDI KinetiZ 7B, the capacitor clearance and 100 MHz FSB makes it an inferior choice. The 7E is a bit better but not much; if you can live with the issues above then it may be considered.

Attachments

Reply 29 of 344, by dj_pirtu

User metadata
Rank Member
Rank
Member

Just bulding myself a DOS/Win98SE/WinXP -machine around KT7A v1.1. I have a Athlon XP Barton @140FSB, 1GB of ECC REG SDRAM, Geforce 5900XT...

BUT, only first 2 PCI slots work, the rest don't. If I put PCI-display card in those 3-6 slots, no picture. Only first 2 slots work.
ESS SOLO-1 sound card don't show up at all and 3COM network says in windows XP 'device cannot start' if put in slots 3-6.

Everything else works.

Bad caps or is this just broken? Don't want recap this if it's not going to help.

Reply 30 of 344, by chrismeyer6

User metadata
Rank l33t
Rank
l33t

That sounds like a recap is probably in order. Also just give the board a close inspection to insure there are no damaged components or traces. Also make sure there's no debris in the pci slots. I'd also make sure the bios battery is good I have two of these motherboards and when the battery gets low or dies they do some really weird and crazy things.

Reply 31 of 344, by dj_pirtu

User metadata
Rank Member
Rank
Member

Battery is new, can't find any damaged traces, scratches or components... There's 3 bad caps near AGP-slot, others are looking good but that doesn't probably mean that those are ok.

Feels really stable all around, 1GB memory with 2 sticks works no problem and so on, only those PCI-slots are dead.

So recapping it is.

Reply 35 of 344, by chrismeyer6

User metadata
Rank l33t
Rank
l33t

Excellent News!!! I'm really glad you got this board fixed. I built my 6 year old son a system based on this motherboard and it's very fast And extremely stable. Enjoy your system and post some pictures of the build!!!

Reply 37 of 344, by JSO

User metadata
Rank Member
Rank
Member

Greetings.

I had bought last October a KT7 rev 1.01 board with a Duron and I was excited, but I found that the KT7a Raid was more versatile, so I bought one fully repaired with brand new capacitors.

I flashed the latest bios and I'm using it alongside
AMD Mobile Athlon 4 1000 - AHM1000AVS3B cpu. The results are fantastic using setmul or lower voltage and frequency. I think that's a better build for DOS compatibility and lower speeds than my previous K6-3+ build, or my Voodoo 3, Slot A build.

I want to now if I can use newer Athlon XP mobile cpus without issues.

DOS IS THE POWER OF OUR CHILDHOOD MEMORIES!

Reply 38 of 344, by cde

User metadata
Rank Member
Rank
Member

You can use the latest Athlon XP mobile without issues (I tested the AXMH2500FQQ4C for instance), however you'll be limited in all cases to 1666 MHz without a FSB overclock, and the BIOS will not display the full name of the CPU. The softmenu BIOS defaults are suboptimal, consider enabling 133/33 MHz FSB, and also set the multiplier to user defined -> 12.5x. Depending on the grade of your CPU, you should be able to bring the voltage quite low, the best I could do is 1.25V.

Reply 39 of 344, by mockingbird

User metadata
Rank Oldbie
Rank
Oldbie

Thank you for your great post. It has been a very good resource for me over these past few months, and I have some observations and critiques to offer.

cde wrote on 2019-06-09, 10:01:

The purpose of this computer is to be able to play DOS and Windows games from the late 80s to the early 2000s. It is not period accurate.

I decided against that kind of system and I built a separate 486 on an Asus VL/I-486SV2GX4. That system is strictly a VLB/ISA, FAT16, DOS 6.22 system. You just can't have a one system does it all kind of computer. You will encounter incompatibility at some point or another.

Motherboard: Abit KT7A
I chose the Abit KT7A for its one ISA slot. It was updated to the latest BIOS (no longer available on abit.ws but still mirrored in a number of places). The VIA 686B is supposed to have a bug with PCI latency but I haven't felt it so far, presumably because I don't use a PCI sound card. Also I suppose the latest BIOS has a workaround, as well as Windows XP SP3 (on the other hand, Windows 98 SE needs the VIA 4in1 4.43 driver to get the fix).

There's a lot of people who want to know whether a 1.3 revision KT7A is required for Barton. No, it is not, as long as you do the following: 1) modify the BIOS to accommodate them, 2) solder the pins on the bottom for the multiplier and FSB (I used 16x133 = 2133Mhz), 3) Find a CPU with an unlocked multiplier (datecode <0338 or so). I am using a 1.1 revision, and it's perfectly fine.

after recapping, the KT7A-RAID is back to working with up to 512 MB of memory without issues. More than 512 MB memory leads to errors in memtest86. This is a problem specific to this motherboard as another one will work without issues with 1.5 GB under XP or Linux. I also recapped a third, badly damaged KT7A but did not regain full usability - see /viewtopic.php?p=818073#p818073

I also re-capped my board, I do not have these issues.

CPU: Athlon XP-M "Barton" 2500+ (AXMH2500FQQ4C) […]
Show full quote

CPU: Athlon XP-M "Barton" 2500+ (AXMH2500FQQ4C)

Has a fairly low TDP (45-53W) and is specified for 1867 MHz however the KT7A BIOS only goes to 12.5x multiplier (1666 MHz). This particular CPU can be undervolted to an insanely low 1.2V @ 1666 MHz (1.25V in BIOS, there is a 0.5V offset for some reason) and consumes very little energy, which allows reducing the fan speed without elevating temperatures. Frequency can be brought down to 500 MHz in the BIOS. Together with disabling L1 cache the speed can be brought down to below 486 DX/33 levels which is great for certain speed-sensitive games.

Unfortunately with this desktop motherboard PowerNow! is not being able to accept a live multiplier change, for example in Linux or with the DOS utilities SETMUL/POWERNOW. That's only a small annoyance because the multiplier can still be changed in the BIOS. The list of multipliers the BIOS offers will depend on the CPU: the XP-M family should have the largest range, and Athlon XPs before week 39 of 2003 should also be unlocked: http://fab51.com/cpu/barton/athlon-e24.html .

I'm not sure overclocking this CPU would make a lot of sense, considering the very slow SDRAM is the primary bottleneck.

Here's what I have to say about the AXMH Bartons... I started off with an unlocked AXDA2800DKV4D (ordinary Barton), and that variant is supposed to run at 2083MHZ (12.5 x 166). Now that would have been nice and fine if this was an AXDA2800DKV4C, which runs at 16x133 by default, but that particular model is rare and expensive. The problem is that the more commonly available (and not to mention affordable) D variants run at a 166Mhz FSB, which requires a DDR-based Athlon XP board (read: no ISA slot), because for one, I don't know that the KT133A does 166Mhz (it probably does), but more importantly, you would need SDRAM that also ran at that speed . So unless you use an unlocked D variant (and mod the pins on the board), your only other options are to somehow find a rare C variant, or underclock your locked D variant, which in the case of the AXDA2800DKV4D would result in a 1667Mhz clock. So I I ran it at 16x133 (2133Mhz), and that is a slight 50Mhz or so overclock (the AXDA2800DKV4D runs at 12.5x166 which as was stated gives 2083Mhz) and that slight overclock required a 100 millivolt boost (1.75V as opposed to the default 1.65V).

So that's why I acquired an AXMH2400, and it is stable at 2133 (16x133), albeit at 1.55V... So that's only 100 millivolts less than what the AXDA2800KV4D runs at at the default clock (or 200mv less if you mod the board to run the AXDA2800KV4D at 2133Mhz). So don't break the bank trying to find one of these mobile chips. It's not worth it. If you're going to use a Barton chip, get the desktop model and mod your socket pins, but unless you plan on significantly underclocking it, use a substantial heatsink. Running Prime95 version 28, even my mobile Barton reaches 45C and more at 2.1Ghz.

Regarding whether the speed is necessary - I think it is. There are situations where a memory bottleneck will not always bottleneck the CPU.

GPU: 3dfx Voodoo 3 2000 PCI
GPU: GeForce4 Ti 4200 AGP

That's something that's unique to each individual. A Ti 4200 is nice, so is a Voodoo3 PCI, and I might put my Banshee PCI in this system, because I don't have a Voodoo PCI and I would like something for Glide, but as for the primary GPU, I'm still debating whether something like a GeForce 2 GTS would be preferable to a Ti 4200 simply because some older games require early nVidia driver versions which don't support the Ti 4200... So that might be an excuse for perhaps yet another build that has such a GPU, and perhaps like you advise, a Ti 4200 or similar in this one.

Sound card: Sound Blaster 16 CT2290 Sound card: ESS AudioDrive ES1868F Sound card: OPL3LPT Sound card: BLASTERBOARD 2.0 […]
Show full quote

Sound card: Sound Blaster 16 CT2290
Sound card: ESS AudioDrive ES1868F
Sound card: OPL3LPT
Sound card: BLASTERBOARD 2.0

I initially opted for a an SB Audigy 2 + ES1869, but changed my mind and acquired an Aureal Vortex 2. The Vortex 2 should provide a better experience, based on what I read. For Wavetable, anything should do for General MIDI to avoid relying on FM synth in DOS.

Storage: Samsung 860 EVO (250 GB) mSATA SSD + Marvell 88SA8052
Storage: SI3114 with Samsung 850 EVO (250 GB) SATA SSD

I spent a lot of time researching the best storage solution. I came to the conclusion that an Ultra 133 TX2 + JMicron Sata to IDE adapter is the ideal solution. Contrary to popular belief, Intel ICH is not fully compatible with the IDE to SATA adapters, at least not with my Intel SSD 530. I tried this with both PIIX4 and ICH2. The main symptom was weird delays during simple write operations in DOS (saving a text file or making a new directory)... Early revisions of the JMicron adapters won't do more than ATA33, so be aware. The Ultra133 TX2 cards need to be re-capped. Once you get everything set up correctly, you won't have to settle for mechanical drives anymore, and TRIM can be run with this setup from DOS on occasion.

Storage: NEC IDE DVD ND-4570A / ND-4571A

I went with the identical model... The foam on the faceplate should be removed and cleaned because it will have disintegrate by this point and turned to a gooey brown substance.

Storage: Gotek with HxC2001 and FlashFloppy

For floppies I wanted the real thing. 1 x 1.2MB, 1 x 720KB, 1 x ZIP 250, 1 x LS120...

Miscellaneous PCI card: 3Com 3C509B / NEC USB 2.0

How are you going to use the 3C509B concurrently with the SB16 with only one ISA slot? I opted for a 3C905 (PCI), and I simply removed the PLCC EEPROM with a hot air gun.

Anyways, I have a lot more work to do... I'm still waiting for parts to arrive, and this has been a long work in progress... But as long as everything works properly in the end, this system is seeming like what I'll be settling on.

Thanks again.

mslrlv.png
(Decommissioned:)
7ivtic.png