Re: My Ultimate 486 (Almost Finished)
Posted on 2011-10-30, 02:07
Final results with Cyrix 5x86 120. BTB_EN and FP_FAST
Re: Potentially F##KED gainbery 5x86 120, options
Posted on 2011-10-30, 01:50
Is the Speedsys memory bandwidth reporting accurate? On my 486 VL/EISA board it reports 245MB/sec. Even though L1, L2 and main RAM scores come nowhere near this.
Re: So you want a Cyrix 5x86-133?
Posted on 2011-10-30, 01:45
I've been running my Cyrix 5x86-100 S1R3 for quite a while at 120MHz at 3.45V, and I haven't encountered any stability problems yet. Though I am using a cooling fan in addition to the stock heatsink. I'm definitely not going to be qualifying for the world's fastest 5x86-120 though, as I'm using a …
Re: So you want a Cyrix 5x86-133?
Posted on 2011-10-29, 02:43
For the most part: 5x86 = Cyrix 5x86C = IBM st5x86 = SGS Thomspon They are mostly similar, except that the IBM chips had better quality control, and the ST chips normally had 4X multiplier. I suppose that the gainberry units may only use the IBM chips. But I am not using a Gainberry kit. I have two …
Re: So you want a Cyrix 5x86-133?
Posted on 2011-10-29, 00:45
You don't have 5x86Cs? You posted a photo of it at the top of this thread! CTCHIP is a pretty interesting program. It isn't just for 5x86 chips. It supports various types of CPUs, and motherboard chipsets. I guess for the most part it does the same thing as the Peter Moss utility, but you should …
Re: Vintage Build
Posted on 2011-10-28, 03:55
You *may* be able to get away with 3 VLB cards at 33MHz. You may be asking for problems if you run the bus speed higher than that.
Re: Upgrading NEC V20 processor to NEC V30?
Posted on 2011-10-28, 01:48
I strongly advise against using an FPU with your 12MHz chip. The relationship between the 8086/8 and 8087 is apparently quite a bit different than with later x86 designs. As it turns out, the 8087 runs more in parallel than as a coprocessor. Even when the 8087 is not in use, it puts out impressive …
Re: Upgrading NEC V20 processor to NEC V30?
Posted on 2011-10-27, 23:52
Nope. It can't be done. The V30 uses the same pinout as an 8086. The V20 uses the same pinout as an 8088. If you want to use a V30, you will first need an 8086 motherboard.
Re: Weird AT-case, any good ?
Posted on 2011-10-27, 02:56
No. It's a Miro Crystal 32S VLB with S3 968 chip. And you are correct, it is indeed S-video TV out.
Re: Weird AT-case, any good ?
Posted on 2011-10-27, 02:49
It's 4MB. Looks like it might be an Elsa Winner 2000 VLB. The port is probably for a microsoft bus mouse.
Re: SB 2.0 CT1350 CMS chips dumped
Posted on 2011-10-26, 03:17
Wow. Great news.
Re: My Ultimate 486 (Almost Finished)
Posted on 2011-10-25, 22:11
I was comparing performance of Cyrix 5x86 and AMD 5x86 using Grand Theft Auto 1 for real world results. Despite the fact that the Cyrix 5x86 at 120MHz whoops am5x86 at 160MHz on speedsys results, in GTA1 the am5x86 at 120MHz was noticeably faster than the Cyrix at 120MHz with enhancements enabled. …
Re: 386DX40 vs 486SX33
Posted on 2011-10-25, 22:06
Check the cache and DRAM timings in the BIOS setup.
Re: 386DX40 vs 486SX33
Posted on 2011-10-25, 15:20
Does your 386 have any cache? Are the memory timings set correctly? Do you have a decent graphics adapter? Not all 386s are built equally.
Re: tualatin motherboard
Posted on 2011-10-23, 03:52
I don't know. I was quite fond of Aopen motherboards. VI15G was a very reliable 486 board, and AP5T was a great Pentium board. At one time I owned both of them and I regret having sold them. Some of their accessories were also quite decent. At one time they made some very sturdy and attractive …
Re: My Ultimate 486 (Almost Finished)
Posted on 2011-10-21, 02:51
D'oh, My previous setup with overclocked DRAM and disabled L2 cache has proven to be almost, but not quite stable. I have reverted back to my previous setup with L2 cache enabled. Just for the hell of it, I decided to try enabling writeback L1 cache. Perhaps if I were running IDE I could get away …
Re: Cant get my motherboard work -> no display..
Posted on 2011-10-21, 02:43
I just realised I have the same motherboard as you. Yours is using an NEC V30 is it not? *UPDATE* I see from your photo again your board uses V20, therefore my BIOS is not directly exchangeable.
Re: My Ultimate 486 (Almost Finished)
Posted on 2011-10-20, 03:11
I have made some further progress with the Cyrix 5x86. I ended up going back to my Cyrix Stepping 1 Revision 3 chip, as it seems to be stable at 120MHz with BTB enabled. This is preferable, as I would like BTB to work in Windows. I also made a strange discovery with my memory settings. I was able to …
Re: My Ultimate 486 (Almost Finished)
Posted on 2011-10-18, 04:25
All you need is a voltage regulator to drop 5V down to 3V (see photos above). The jumpers for controlling the multiplier are part of the VRM. However, you can pretty much forget about using writeback cache mode (L1), and linear burst. I was however able to get a number of the other enhancements …
Re: So you want a Cyrix 5x86-133?
Posted on 2011-10-18, 03:39
I found a way to get my 5x86 into 3x mode. After booting up at 2x, I set the CPU into 1X mode, then change the CLKMUL pin to 3X, and then set the cpu into 3X mode using ctchip. I plan to rig up a jumper cable to my vrm adapter to make this practical.
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