Re: memtest86 that works for 486
Posted on 2019-11-25, 11:47
I have been using Memtest86+ 4.10 with 386 and newer hardware without problems.
Re: Crystal FM disable
Posted on 2019-11-25, 06:53
In Windows everything changes, a driver can trap any IO port and do whatever it wants with it before the hardware actually gets to see any action, if at all. The current problem is likely driver doing full init to how it sees fit, ignoring any hardware configuration that EEPROM dictates. If you're …
Re: Crystal FM disable
Posted on 2019-11-25, 02:57
You probably need to patch the Crystal driver so it wouldn't intercept FM stuff...
Re: Video memory upgrade, not sure which chip to get
Posted on 2019-11-24, 09:13
That is true on PLCC chips but SOJ are perfectly symmetrical and there's nothing stopping you from inserting them the wrong way. I have seen plenty of burned sockets and memory chips, all from someone inserting the chip wrong way.
Re: Video memory upgrade, not sure which chip to get
Posted on 2019-11-24, 03:52
Those memory chips should work perfectly, just pay attention to Pin1 on both socket and the chip or there will be destruction.
Re: Why does EMS suck on my 286?
Posted on 2019-11-24, 03:50
The final solution is pretty nice still, congrats ~
Re: What retro activity did you get up to today?
Posted on 2019-11-22, 22:06
Sounds like fun. Out of curiosity here, does the driver enable UMBs on certain chipsets? It is completely chipset specific, I'm starting with Intel Aries (420EX) but todo list has SiS471, SiS496, ALi M1489 and OPTi895 also (basically hardware I have, that also has chipset documentation available). …
Re: What retro activity did you get up to today?
Posted on 2019-11-22, 15:24
I spent most of the day on making an actual DOS device driver, with intent to get UMBs going on several 486 chipsets (or anything else i can find documentation on). Thänk you to Uwe Sieber (UMBPCI author) for crucial info ~
Re: Port 80 POST card in XT
Posted on 2019-11-22, 07:34
It could be that all the board's internal peripherals' (DMA, PIT etc.) access cycles don't produce an ISA cycle.
Re: 486 cache trouble shooting ?
Posted on 2019-11-22, 00:51
That will not work, at best you have instant crash when BIOS tries to enable cache. Entire bank needs to be present, just like with RAM.
Re: AWE64 WaveSynth effects?
Posted on 2019-11-21, 08:26
The PCM stream can go through EMU8000 side on AWE64 so there isn't any need for software based effects, only mixing.
Re: Fastest 486 CPU with 8k L1?
Posted on 2019-11-19, 17:43
Even WB CPUs support WT, this is set by state of one pin during reset and that pin is generally set so that on a board that doesn't support WB the CPU starts in WT mode.
Re: Packard Bell CRT Monitor Issues
Posted on 2019-11-19, 03:44
Better monitors have magnetic shielding cage around the tube so that they are much less sensitive to external fields. Neck area is the most sensitive part since small change there gets amplified dramatically by the deflection later on. These screwdrivers shouldn't cause any sort of pulsations though …
Re: Upgrade path for 486DX-50
Posted on 2019-11-18, 21:33
If there was no 5V limit you can run a DX4 at 2x multiplier with 50MHz FSB very nicely.
Re: Packard Bell CRT Monitor Issues
Posted on 2019-11-18, 13:04
If you don't have any 50/60Hz transformer nearby the rear of the monitor (they create a changing magnetic field that could cause such a jitter) there's likely some electronics problem in it and if capacitor change is as good as dead, all other things involving testing and swapping stuff in it are …
Re: Adding a Fan to the Voodoo 3000? Powered by the card?
Posted on 2019-11-15, 21:26
First you need to make sure they actually are 5V lines, rather than some digital signals. Multimeter will not be able to tell a difference, outside actual continuity check against 5V elsewhere such as HDD or mobo power connector. Safest locations are the various tantalum capacitors, they are …
Re: Adding a Fan to the Voodoo 3000? Powered by the card?
Posted on 2019-11-14, 23:18
Best place to take power is from the various tantalums or fat ceramics which are gonna be sitting between some power rail. I used a big cap near the voltage regulator chip for fan power on my Banshee card :
Re: Why do some YMF71x cards have two crystal oscillators and why do some have only one?
Posted on 2019-11-14, 14:07
If you only seek "FM daughterboard" then the missing crystal won't make a difference. It starts mattering only in Windows where you might actually play a music file or video or something that uses 48KHz based sample rate. The first card will need a more elaborate mod to get 48KHz support, the second …
Re: Why do some YMF71x cards have two crystal oscillators and why do some have only one?
Posted on 2019-11-14, 13:55
33.8688MHz for 44KHz based rates, internal state machines, FM and SB section, 24.576MHz for 48KHz based rates only.
Re: Why do some YMF71x cards have two crystal oscillators and why do some have only one?
Posted on 2019-11-14, 13:41
The ones with single crystal do not support 8, 16, 32 and 48KHz properly (33.8688MHz is used in place of the proper 24.576MHz leading to much higher pitch on those rates), those cards are cheaped out versions that should be avoided or if you can, add back the missing 24.576MHz crystal to get proper …
Page 94 of 150