Re: Ever Seen this one?
Posted on 2024-04-08, 08:20
Cirrus Logic & Trident focused on miniturisation/less components... They have all kinds of power, but ~one year out of top performance v the competitors.
Re: ISA vga card works only in 8-bit mode
Posted on 2024-04-07, 07:32
It looks like the main processor is an 8-bit chip judging by it's size. If placing a jumper on 0-Wait-State does nothing, you could try using Bus Clock Divider settings in Bios if present. Eg. BusClk / 2.
Re: Interposer between Cyrix 486 and motherboard
Posted on 2024-04-06, 06:48
The bad news is that the system is a bit underperforming. [...] ... CacheCHK doesn't seem to recognize the 2KB cache at all (see pic). Before working further on this setup, I need to dig up some old utilities for the Cyrix CPUs. The one I used for the 486DLC doesn't appear to be working with the …
Re: Why would you need 3x 2kb tag-ram chips for 16kb of L2 cache in a 386?
Posted on 2024-04-04, 14:36
This is 256KB using 3 TAGs with 22pins. W22B65AK-20. Can't find the datasheet anywhere so they may/may not be 64KBx4, and whether or not they have comparator. From an ECS SL486VE board.
Re: A Mystery, hoping someone can solve for me
Posted on 2024-04-01, 12:38
This is a similar board (top photo is of a board I sold recently): https://theretroweb.com/motherboards/s/unknown-612-3035-001 The CPU can be upgraded to a TI486SXLC2-50 without any bodge wires to get the cache working.. solder it in and run the Cyrix utilty to turn on double clock mode... and done. …
Re: Custom interposer module for TI486SXL2-66 PGA168 to PGA132 - HELP!
Posted on 2024-03-30, 10:41
In the "1994_TI486SXLC_and_TI486SXL_Microprocessors_Reference_Guide", pages 209-210, For the TI486SXL-G(40/50/66): Absolute max VCC is 5.5V Absolute max temp is 110C (power applied), 150C storage Recommended max VCC is 5.25V Recommended max temp is 85C (power applied) 5.25V should be "guaranteed" if …
Re: Anyone Interested In Determining The Pinout Of An IBM 486SLC3?
Posted on 2024-03-29, 05:55
This page here says the SCL3 (16bit) is a DLC (32bit) chip except with the extra address pins disabled. "All known instances of 486SLC3 CPUs are reportedly in the 132pin PQFP packaging with the extra address lines not connected (a 486BL3 running in 16-bit mode)" https://alchetron.com/IBM-386SLC Not …
Re: Custom interposer module for TI486SXL2-66 PGA168 to PGA132 - HELP!
Posted on 2024-03-27, 12:51
A large 3A diode inline before the VR could drop voltage by a volt or two... but maybe a different type of regular would be beter, like a switching regulator.
Re: Custom interposer module for TI486SXL2-66 PGA168 to PGA132 - HELP!
Posted on 2024-03-27, 07:27
The sum used in the AP7363 datasheet says: Power Dissipation PD = (VIN - VOUT) × IOUT PD_Max = (Shut Down Temp - Ambient Temp) / Resistance of Terminal to Ambient in deg per watt.
Re: Custom interposer module for TI486SXL2-66 PGA168 to PGA132 - HELP!
Posted on 2024-03-27, 07:23
PODs take 5V in, why use a regulator at all... I still don't see a problem with my VR design... For a 3.3v 1Amp (typical worst case) CPU draw, the datasheet says Power Dissipation required is 1.7W, Max Power Dissipation possible for the SO-8EP package to the copper area is 2.36W (25C day), and 2.0W …
Re: Custom interposer module for TI486SXL2-66 PGA168 to PGA132 - HELP!
Posted on 2024-03-26, 15:39
Looking good. Is the fan normally on the interposer 5V? They put out quite a lot of noise. I don't think which ground matters, may be slightly cleaner using the PSU/molex ground. Modern GPUs and CPUs have their own independant power going to the PSU.... I thnk when you use multiple AC-DC converters …
Re: Custom interposer module for TI486SXL2-66 PGA168 to PGA132 - HELP!
Posted on 2024-03-26, 06:06
There's smaller versions of the LDO regulator I'm using that are still rated for the same spec. The solder/thermal pad is connected to the entire top layer and stitched with 18 nearby vias to the central large GND plane, and bottom layer. This is the datasheet (in SO-8EP): https://www.diodes.com/ …
Re: Custom interposer module for TI486SXL2-66 PGA168 to PGA132 - HELP!
Posted on 2024-03-25, 12:46
The only connections I can see on the folded/flexible circuit to the CPU are Flush, HLDA, VCC, GND... HLDA can be used with MEMW to activate Flush, but it seems to be doing it without MEMW. After a certain amount of clocks has passed while HLDA is active, Flush is activated? Not exactly sure. On the …
Re: Slow 3D video card on super socket 7 shootout (sis 305, savage4, trident blade3d, riva tnt, etc)
Posted on 2024-03-21, 07:15
I was under the impression the CPU ran the main loop in it's L1 and L2 caches and more than texture/memory transfer was going to the AGP port, but fair point...
Re: Slow 3D video card on super socket 7 shootout (sis 305, savage4, trident blade3d, riva tnt, etc)
Posted on 2024-03-20, 11:05
It's an AGP 2x motherboard. WIth AGP 4x, the TNT2-M64 should be +40% faster, and the Geforce 2 MX-400 should be +200-400% faster. Haha, no! Not even on faster CPUs. You are looking at couple percent at max. Look at platforms memory bandwidth to get a perception of scale, even x2 is too fast for K6. …
Re: 486 SocketBlaster building experiment - Oh my God, a difficult beast to build
Posted on 2024-03-20, 10:27
The ripple voltage can be a lot higher than you think. This is the highest Output LOW voltages acceptable for a DX4-100 3.3V CPU: IOL = 4.0 mA (Address, Data, BEn) ... 0.45V IOL = 5.0 mA (Definition, Control) ... 0.45V IOL = 2.0 mA ... 0.40V IOL = 100 µA ... 0.20V Lowest Output HIGH voltage: IOH = …
Re: Turbo button, slowdown programs, disabling cache - only for games?
Posted on 2024-03-20, 10:00
Flashing cursors in DOS and DOS-based word editors might be disorientating if the CPU is faster than BIOS/DOS thinks it is, too.
Re: 486DX4 at 5v… instantly fry?
Posted on 2024-03-18, 09:32
You need to check the "absolute max" DC ratings for the exact CPU you're testing. One DX4 manual I'm looking at says 4.6V max. With "Extended exposure to the Maximum Ratings may affect device reliability."
Re: Slow 3D video card on super socket 7 shootout (sis 305, savage4, trident blade3d, riva tnt, etc)
Posted on 2024-03-18, 09:16
It's an AGP 2x motherboard. WIth AGP 4x, the TNT2-M64 should be +40% faster, and the Geforce 2 MX-400 should be +200-400% faster.
Re: U-Board ST1A JK-042e settings with Intel DX4-S, not booting at 100Mhz.
Posted on 2024-03-15, 18:17
Does the board have an Intel/AMD jumper? AMD DX2/DX4 (non WB) have a different CLKMUL pin than Intel and others. http://www.pchardwarelinks.com/486pin2.htm
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