Yeah, the 40mhz bus setting should get you to 100mhz, if your chip can handle it. And I understand that to be kind of a big 'if'... apparently a lot of them just won't do it.

That's interesting and I wonder which one would end up faster:

Overclocked AMD 486-133 or overclocked Intel POD 83?

Mau1wurf1977 wrote:

That's interesting and I wonder which one would end up faster:

Overclocked AMD 486-133 or overclocked Intel POD 83?

Assuming the Pentium OD can be overclocked at all, I would say the POD in most cases. At 160mhz, the AMD chip is roughly equal to a P90. It probably wouldn't be hard to get another 7mhz out of a POD and maybe more. Even if you have one of those rare motherboard/chip combinations that will run stable at 180mhz, that probably still only puts at around 100-110mhz Pentium equivalent and a POD 83 should get there without much tweaking. It's only 17-27mhz more. A 40mhz bus with a 2.5x multiplier or a 3X multiplier with cooling would probably be doable assuming Intel didn't lock it. Even a 33mhz bus with 3x multiplier would get you to the maximum that the AMD chip can do.

It looks like I'm in luck, and the BIOS settings are completely maxed out, including a RAM read = 0 speed and 2-1-1-1 cache speed. Looking at the Speedsys result, even the CF result is cool. Cachechk(7) confirms that the machine is using L1 and L2 cache - pod.txt report attachment below.

At the moment, I'm using a crappy ISA VGA card. I'll remove it, and replace it with a PCI card, run 3DBench, then loosen up the cache timings a little, and run Quake. Then, I'll loosen up the BIOS timings a bit more, and run Wintune97 inside Windows 95...

What's your motherboard?

sliderider wrote:

What's your motherboard?

This one. 😀

sliderider wrote:

At 160mhz, the AMD [5x86] is roughly equal to a P90.

As long as we're not talking 3D games. In that case it might be only a bit more than half as fast...

However, the 486 POD also has the added bottleneck of having around quarter the bus bandwidth on a 486 board (maybe less in practice). With its normal bandwidth and cache advantages gone, for non-FPU stuff it's around the same speed as a 486 at the same clock speed. But if you use the FPU it's still considerably faster because the FPU is less sensitive to memory performance. I saw these results when I was playing with a Voodoo3 in my PCI 486 board comparing the Cyrix, AMD and POD chips.

This is really interesting, and a bit disappointing too. I can't get Quake working, if I overclock the POD 83. I've loosened up the BIOS settings a lot, but that doesn't help. Quake runs for about a second, then quits back to the C:\ DOS command prompt. Initially, I thought that this POD 83 chip was going to overtake my OC'd AMD 5x86 chip, but it looks like running DOS Quake 1 is a good test to check for stability.

Message to overclocked POD 83 owners - please try running Quake 1.06 (free download shareware version), and see if you can get it to run at all, and if you can, what is your timedemo demo1 score? Thanks a lot.

Wow, this POD 83 chip has just jumped back in to pole position, for the 486 DOS Quake 1 test. With this POD chip not overclocked, and the mobo's BIOS settings completely maxed out, I get 18.3 FPS in Quake 1, and that's in Full screen! That's faster than an AMD 5x86 P75, insanely overclocked to 50 MHz bus speed, with a 4x multi, to equal 200 MHz CPU clock speed. For that configuration (admittedly using a different 486 mobo - and I'll redo this Quake test on this currently used mobo with that AMD config), I got 17.7 FPS.

Edit: I expect Quake runs better on this "Pentium hybrid" chip, because id software wrote this game for the Pentium. For example, I've just run 3DBench and PcpBench on the non-overclocked POD, and I get slower scores, compared to the OC'd AMD chip. 3DBench = 83.3, and PcpBench = 9.0. However, I expect that I could OC the POD chip, and it not fail and also get slightly better scores for these utils, and other games. But for Quake, it looks like the (non-OC'd) POD is the champ.

You need to run the full battery of torture tests and see what the results are. This could look promising for owners of older 486 rigs needing to wring a little extra speed out of their systems for some of the more demanding games but who don't want to have to build a P54 system to run them.

retro games 100 wrote:

Message to overclocked POD 83 owners - please try running Quake 1.06 (free download shareware version), and see if you can get it to run at all, and if you can, what is your timedemo demo1 score? Thanks a lot.

It has been like 5 years since I played with the POD but I'm pretty sure I had Quake working at 100. I also had Jedi Knight going.

POD at 100 is tricky though. The motherboard may be a factor in its stability at that speed too.

So in a nutshell for 386/486 coded applications, the AMD 133 was a good alternative, but once you run Pentium coded software, the POD leaps ahead?

It's most obvious with 3D games because they use the FPU. It was rare for a game to use it until that point. The Pentium FPU is a giant leap ahead of any 486's.

This was also a huge oversight for the Pentium competitors like AMD K5 and Cyrix 6x86/MII. They have horrible FPUs that perform like a 486's and so can not touch a Pentium for 3D games.

Theres one significant drawback if you compare POD-83 overclocking and 5x86 overclocking: You can't up the voltage of the POD since it runs on 5v already.

Btw RG, hows the noise of the little Intel fan on that thing?

I never had any luck with overvolting 486s.... Some boards have 4v setting but it didn't really help. 5v would probably blow these 350nm chips up.

You can't up the voltage of the POD since it runs on 5v already.

Externally, yes, though there is a way of modifying the onboard voltage regulator to change the voltage going to the chip itself. I'll be damned if I can remember the details of it, though, and I also recall it making little/no difference in the overclocking ability.

One other random tidbit about those things... IIRC they automatically switch to a 1X multiplier if you remove the built-in fan. (You'd want to attach an externally-powered fan in its place though.) That might provide some possibilities for testing a 66mhz bus speed.

Old Thrashbarg wrote:

You can't up the voltage of the POD since it runs on 5v already.

Externally, yes, though there is a way of modifying the onboard voltage regulator to change the voltage going to the chip itself. I'll be damned if I can remember the details of it, though, and I also recall it making little/no difference in the overclocking ability.

One other random tidbit about those things... IIRC they automatically switch to a 1X multiplier if you remove the built-in fan. (You'd want to attach an externally-powered fan in its place though.) That might provide some possibilities for testing a 66mhz bus speed.

I was considering this also, but I'm more interested in fooling the POD to think it's original fan is still attached so I can use another fan 😉

The POD fan sounds OK. It's not too noisy. The POD was new and sealed, so it's working well. Also, regarding volts and 486s, I've got 5V going through the overclocked P75 chip, and no problems to report.

Old Thrashbarg wrote:

You can't up the voltage of the POD since it runs on 5v already.

Externally, yes, though there is a way of modifying the onboard voltage regulator to change the voltage going to the chip itself. I'll be damned if I can remember the details of it, though, and I also recall it making little/no difference in the overclocking ability.

One other random tidbit about those things... IIRC they automatically switch to a 1X multiplier if you remove the built-in fan. (You'd want to attach an externally-powered fan in its place though.) That might provide some possibilities for testing a 66mhz bus speed.

Ummm...there are no 486 motherboards with a 66mhz bus setting. 😉