VOGONS


First post, by VooDooMan

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Some of you might already know this, some of you might just read my previous thread but it seems that SiS 635T chipset is the king of performance among all Pentium III motherboards(single socket)! That is why I think this "forgotten" chipset deserves a little bit more attention 😉

1abascx.jpg

The sad thing about this chipset is that it was used on very few motherboards. The most common one is the ECS P6S5AT which I am using for my tests right now.
There are probably some others too, but they seem very rare or even ghost hardware …
Here are other ones that I’ve found so far:
- PC Chips M700
- Jetway 635CS
- ECS P6S5MT
- ASUS CUS266
The perfect solution for me would be to have the one by ASUS, unfortunately it seems to exist only on paper... IMAGINE ASUS STABILITY/OVERCLOCKING FEATURES and the PEROFORMANCE of SiS 635T! It would be the Ideal Motherboard for all Pentium III CPUs 😀

Lets discuss now the weak and strong points of this ECS P6SPAT mobo.

Advantages:
- The fastest Single Socket 370 platform for Pentium III CPUs when paired with solid AGP graphics card that utilizes AGP features. – Check this thread if you want to see details.
- Provides proper AGP divider with 166 FSB! This feature makes this mobo one of a kind… I think it is the only Pentium III chipset that has such capabilities! So far I was not able to prove it "on paper" as a proof, but I used a simple trick described here and it works. Anyone can check it yourself and see if it works on your ECS, or try on any other Socket 370/Slot1 mobo and see that it doesn’t work. I think they made that divider for 166FSB when they were working on SiS 735 chipset for ATLHONS at the same time, so in a way they are kind of a “cousins” but that is just my theory, and I cannot tell for sure.
- Surprisingly stable! After all the tests I have done there was NOT A SINGLE case of an error or freeze… and I used many graphics cards to check it.
- Boots very fast. I did not measure precisely, but I have an impression that this P6S5AT is the fastest booting motherboard among all Pentium IIIs.
- Very cheap at its release and not that hard to find nowadays.

Disadvantages:
- Really bad caps… I advise you to re-cap it before you use it.
- Very simple and limited BIOS. You cannot set the tRas timing in the BIOS which really sucks. There are NO overclocking features in the original BIOS which sucks even more. All though, I think there was a hacked BETA BIOS in the past that allowed for some overclocking modifications but I was not able to find it anywhere so far… Hopefully somebody here will have more information on this topic and helps me out… 😀
- Poor performance with PCI video cards probably to the fact that there is no south bridge on this motherboard. Everything is integrated in one chip.
- No ISA slots. Old sound cards enthuses will complain on that.

-=OVERCLOCKING=-

Despite the fact that this chipset is BAD for overclocking, it is PERFECT for “already” overclocked processors 😉 Strange as it may sound, but that is true… why? You cannot overclok anything in the BIOS but you can use CMOSTool for some limited OC features. So if you have a CPU that you already overclocked on a different mobo, and you know that it works fine at 150 or even better at 166 FSB than this mobo is perfect for you 😉 At 166, you can use DDR 333 memory so that you do not have to overclock regular 133MHz SDRAM (I am aware of 166 MHz SDRam but it is very uncommon) and the proper AGP divider will not affect your AGP graphics cards. In this case you are overclocking only your CPU without “damaging” other components like RAM, GPU or PCI devices 😀

How to use CMOSTool on ECS P6S5AT for OC?

There aren’t many features that you can change, there is no 1 MHz increasement. I know how to set 150/150 and 166/166 but there are other options too. 200/200 is possible for example, but I guess that is only for some EXTREMER OVERCLOCKERS 😁 I wonder what is the AGP diveder then 😜

To set FSB to 150 MHz: address 0x006F value and set it to 0x0039
To set FSB to 166 MHz: address 0x006F value and set it to 0x003A

As simple as that 😉 It works as long as you change it or reset you CMOS manually on you motherboard.

WHAT PROCESSORS USE FOR STABLE 166 FSB?

I am trying to find any Coppermine/Tualatin CPUs that are able to work flawlessly at 166 MHz FSB. So far I have found only too, and it is described in this thread
Unfortunately, there is probably no way to change the voltage of a given cpu in CMOSTool on this mobo… so in case you find a CPU that is capable of 166 MHz but requires more voltage, you will have to make a volt mod. I tried all of my Tualatin CPUs and unluckily none of them worked at 166 FSB... but most of them had no problems running at 150 FSB.

TEST RESULTS WITH OCed CPUs

Here are some OC results with Pentium III-S Tualatin (SL6BY) at 150 FSB:
GeForce Ti 4600 (Default GPU/RAM clocks):
SLBY150ti4600.jpg
GeForce FX5950 AGP (Default GPU/RAM clocks):
SLBY150fx5950.jpg

Here are some OC results with Pentium III Coppermine (SL5FQ) at 166 FSB

GeForce Ti 4600 (Default GPU/RAM clocks):
1166Ti4600.jpg

GeForce FX5950 AGP (Default GPU/RAM clocks):
2166FX5950.jpg

GeForce FX5950 AGP (OVERCLOCKED CARD!):
166FX5950overclocked.jpg

And here is the "IMPOSSIBLE"
ATI Radeon 9800 PRO overclocked to the speeds of Radeon 9800 XT on a 166 FSB!!!![/u]
x166RADEON.jpg

The same trick with Readon 9500 that won't work on any other socket 370 boards 😉
x166Radek9500OCjestA.jpg

Stability while overclocking is excellent. Once I found a stable CPU I stressed it for 1,5 hour in Everest with positive results. The chipset itself does not get very high, I measured 42 Celsius degrees on the surface of chipsets’ heatsink. The temperatures shown in BIOS seem to be incorrect.

HOW TO LOWER THE RAM TIMINGS?

In the BIOS there is no option to alter the tRAS timing. You can change CAS# Latency RAS# (2-3) RAS to CAS#(5-6) and RAS# Precharge (5-6) but there is no option for tRAS. I tried different software to change it, but none of them worked. I think it will be possible with CMOSTool but I don't know which address is responsible for tRAS and what value should be set to lower it... If I manage to do so, the performance should be even better 😉

What I find difficult is to set the RAM timing to 2-2-2-6 on a 166 Front Side Bus! The best configuration so far I managed to set was 2,5-2-2-6 on some regular CL2,5 DDR400 RAM by GOODRam. I guess I need better RAM... I still have to look for some fast CL2 400 MHz DDR memories to be finally able to achieve 2-2-2-6 and maybe even 2-2-2-5 if I find a way to lower tRAS somehow...

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Reply 1 of 42, by VooDooMan

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THE GOOD PART!

Thanks to my friend "Jenot" from 3dfx.forum.pl I was finally able to lower the RAM timings!

To change tRAS to 5 you have to edit offset 58 and write 10 in bits 7/6 😀 I used WPCREDIT to do that.
There is even option to set tRAS to 4 but it works only with certain RAM sticks.

All the other options are:
Offset 58:
bits 7/6: tRAS (00-6T, 01-7T, 10-5T, 11-4T)
bits 5/4: tRP (00-3T, 01-2T, 10-4T)
bits 3/2: tRCD (00-3T, 01-2T, 10-4T)
bit 1: tRC (0-tRAS+tRP, 1-tRAS+tRP+1)
bit 0: tRRD (0-2T, 1-3T)

Offset 59:
bit 6: tWR (0-2T, 1-1T)
bits 5/4: CL (dla DDR 01-2T, 10-2.5T, 11-3T)
bits 3/2: RW turnaround time (00-safe, 01-normal, 10-fast, 11-ultra)
bits 2/1: read latency (00-safe, 01-normal, 10-fast, 11-ultra)

I also know the reason why this mobo has the proper dividers for AGP and PCI! Everything is explained in this ICS9248-146 clockgen Datasheet

Si-S635-T-clockgen-options-C.jpg

Even though this clockgen theoretically allows to set FSB to 200 MHz it is not included in the CMOS/BIOS Settings.
Here are all the options I examined in the CMOSTOOL("0x006F"):

00= 66/66

01= 66/100
02= 66/133

03= 100/100
04= 100/133

05= 133/100
06= 133/133

07= 138/138

08= 100/150
09= 150/150

0A= 166/166
0B= 100 / ? HARDWARE TRAP! MOŻE maybe it should be 200/200?
0C= 150 / ? hardware TRAP
0D= 133 / 100
0E= 135 / 102
0F = 150 / ? HARDWARE TRAP

The most interesting options are 150/150 and 166/166
When FSB is set to 150 MHz the AGP port runs at 60 MHz (downclock). That justifies why my results at 150 FSB were not so good compared to other motherboards at that speed(150) where their AGP bus is overclocked!

zzzzzzzzzzzzzzzzzzzzzz.jpg


Now the SAD part:

1) I was not able to run any Tualatins with 512kb cache @ 166 at all! There is post, I can enter BIOS, but I won't boot into Windows no matter what!

2) I was able to barely run Tualatin-S 1133MHz with 256kb(!) cache @ 166 but with very poor results and only at CL 2,5-2-3-6!

Results
133 FSB, 2001 MARK - CPU CLOCK = 1400 MHz (512kb cache)
133-Tual-256kb-2001-SE-ECS.jpg

166 FSB, 2001 MARK - CPU CLOCK = 1416 MHz (256kb cache)
166-Tual-256kb-2001-SE-ECS.jpg

133 FSB, SiSoft RAM test - CPU CLOCK = 1400 MHz (512kb cache)
133-Tual-256kb-memtest-ECS.jpg

166 FSB, SiSoft RAM test - 1416 MHz (256kb cache)
166-Tual-256kb-Mem-Test-ECS.jpg

We can compare the results of those two CPUS"
- 2,78 % gain... in 3D Mark (9787 - 10055) on 166 FSB but with less cache
- 52,3 % gain! in SiSoft RAMtest (409 - 623) on 166 FSB but with less cache

3) This mobo seems to run Coppermines! at 166 WITOUT any problems but only with certain RAMs and at CL2,5 maximum (CL2 won't run at all or won't be stable)

This is what baffles me the most. Why is it so, that Coppermines generally run pretty well at 166MHz while Tualatins won't accept that speed? Is it because of the chipset limitation? Or maybe the BIOS needs some updates? It's also important to notice that 166 is fine when the CL timing is 2,5 maximum, 2 is very unstable. I tried DOZENS of RAM sticks! Usually the "fancier" ones won;t run at all... the ones with no name or no markings on the sticks ran better. I recommend GOODRam for this mobo - thier RAM caused me less problems than others.
There is also a theory that maybe RAM on this mobo needs more voltage - it runs at 2,5V at default and maybe this is not enough. There is no option to change that by software so to check that I would have to physically MOD the RAM to let's say 2,7V and force it to work it like that on that board.

4 I can't find that legendary custom BIOS that would allow for Overclocking in BIOS nowhere in the internet... I tried to find someone who would like to mod that BIOS for me but with no luck so far...

TESTING on Windows XP!!!

Lets check the performance of the FASTEST SINGLE SOCKET 370 motherboard and some FAST AGP cards from different generations. Of course installing anything faster than GeForce 4 ti 4600 seems pointless here, but I just wanted to see the differences between those GPUs with such a "slow" processor.

Here you have a chart with all the results in one place.
0-ALL-in-a-table.jpg

2001SE MARK
2001-SE-Si-S-635-T-cards.jpg

Partial results here: 3DMark01 Mega Thread

2003 3D Mark
2003-Si-S-635-T-cards.jpg

Partial results here: 3DMark 2003 Mega Thread

AQUAMARK
Aquamark-Si-S-635-T-cards.jpg

Partial Results link: RetroGraphicsCards

DOOM 3 Low settings 640x480
Doom3-LOW-6x4-Si-S-635-T-cards.jpg

DOOM 3 Ultra settings 12x10
Doom3-ULTRA-12x10-Si-S-635-T-cards.jpg

FarCry Low settins 12x10
Far-Cry-LOW-12x10-Si-S-635-T-cards.jpg

FarCry MAX settins 12x10
Far-Cry-ULTRA-12x10-Si-S-635-T-cards.jpg

Serious Sam Direct 3D
Serious-Sam-Open-direct-3-D.jpg

Serious Sam OPENGL
Serious-Sam-Open-GL-12x10.jpg

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Reply 2 of 42, by Kami27

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Hello VooDooMan, I just finished reading the other thread about the ultimate single S370 mobo and this one, thanks a lot for all your work! I managed to get this ECS board locally last month before knowing about what you experienced with it. Unfortunately, I'm a bit stuck overclocking wise... You talked about a software called CMOSTool to overclock the FSB but I really can't find it anywhere, could you help me please ?

Another question: have you been able to get the bios modded by some nice folk ?

I was wondering if it was possible to add support for the PLL in softfsb or setfsb (I didn't use them extensively TBH)... and potentially doing this for lots and lots of motherboards, editing a "new" version of one of these softwares to make life easier for retro overclockers, a bit like CPU-Z vintage edition from CuPid here on Vogons. It could be a nice thread to do, though maybe someone has already thought about it, I'll look for that

Reply 3 of 42, by Nemo1985

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I'm sorry for the bump, I finally found this motherboard, but it seems a bit different from the one in the picture, is it an older revision probably?

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What do you think?

Reply 5 of 42, by Nemo1985

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BigDaddyM wrote on 2021-01-28, 22:20:

I Think it is 1.5 revision. Tualatins are supported on 1.6. You can check in corner od the board, near ram slots

Thank you for the tip, I will check as soon I will get the mb, well that's not a good news :\

Reply 7 of 42, by Nemo1985

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BigDaddyM wrote on 2021-01-29, 07:42:

Sorry but I was wrong, revision 1.5 does support tualatins 😀

Well good news 😁
Do you know what are the differences between the different revisions?
Thank you

Reply 8 of 42, by BigDaddyM

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Well, i own few 1.6 and one 1.5 revsion. I did not notice any differences between the revisions apart from the PCB color 😀 Brown version is always 1.5, but black can 1.5 or 1.6. There should also be a 1.3 revision but I've never seen one like this. I don't know how they differ but I know they can work with many broken capacitors 😀 😀

Reply 10 of 42, by Nemo1985

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I just received the motherboard, I can confirm it's a Rev 1.5A.
Ecs has updated the website, any advice where I can find the latest bios?

Edit: the mb doesn't work, it throwed E0-- error a couple of times and then now it shows -----, I tried to change the cpu and ram, but no results :\

Reply 11 of 42, by chrismeyer6

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Have you checked to make sure the bios battery is still good or has one installed? I've had many a motherboard that would refuse to post or just act really weird if the battery was low/dead or Missing. You can also try clearing the bios setting as well.

Reply 13 of 42, by Nemo1985

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I have finally been able to recap the ecs board and brings it to a new life.
As I always do I checked the microcodes and I noticed a weird thing, some of them are duplicated there are more version of the same microcode so I took the chance to remove the duplicates and update the others with the latest version.
I also spotted in the bios a hidden setting which let the system choose the updated ones, that explain the reason of the duplicates, I also made visible some more settings like ide busmaster and the boot speed selection.

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Reply 15 of 42, by Nemo1985

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This board is driving me crazy.
I swapped the cpu and memory (p3 866-p3 1000 and 256 ddr to 256 sdram) and now the board doesn't work anymore, the debug card shows once again the ---- code, how is it possible?
I tried to clear the cmos, use the vanilla bios instead of the updated one and from what I understand the cpu gets worm.

Reply 16 of 42, by VooDooMan

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Sorry, I haven't checked in here for a while...

Kami27 wrote on 2020-08-21, 17:32:

You talked about a software called CMOSTool to overclock the FSB but I really can't find it anywhere, could you help me please ?

If you are still interested please write me a PM.

Kami27 wrote on 2020-08-21, 17:32:

Another question: have you been able to get the bios modded by some nice folk ?

No... I am still hoping that somebody here is going to share it one day 😉

Nemo1985 wrote on 2021-01-29, 09:52:

Do you know what are the differences between the different revisions?
Thank you

Well, I don't know what the exact differences are (all revs look the same besides the collor of the PCB) probably there are some changes within the chipset itself and maybe in voltages. All I know is the higher REV the better chances that Tualatins are going to work properly 😉

Nemo1985 wrote on 2021-03-09, 03:30:

As I always do I checked the microcodes and I noticed a weird thing, some of them are duplicated there are more version of the same microcode so I took the chance to remove the duplicates and update the others with the latest version.
I also spotted in the bios a hidden setting which let the system choose the updated ones, that explain the reason of the duplicates, I also made visible some more settings like ide busmaster and the boot speed selection.

Thank you! This is interesting! I'll have to try it! Are you able to make some more changes in the BIOS? 😜

overdrive333 wrote on 2021-03-09, 05:42:

To run tualatin at 166fsb you need 1.0A b-stepping cpu - SL6CB or SL6JQ
Or SL68V ( 900mhz) https://overclockers.ru/lab/show/15001/Celero … _eto_fantastika

I don't think that is the case... I tried to run Tualatins that work flawlessly on other boards at 166, but they just won't run on this one... I have no idea why it is so that Coppermines at 166 run on this mobo but Tualatins don't... I guess I am just too stupid to comprehend that 😀

Nemo1985 wrote on 2021-03-11, 06:45:

This board is driving me crazy.
I swapped the cpu and memory (p3 866-p3 1000 and 256 ddr to 256 sdram) and now the board doesn't work anymore, the debug card shows once again the ---- code, how is it possible?
I tried to clear the cmos, use the vanilla bios instead of the updated one and from what I understand the cpu gets worm.

That is not good... Were you able to bring it back to life?

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Reply 17 of 42, by Nemo1985

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Glad you are back 😀

VooDooMan wrote on 2021-04-08, 07:39:

Thank you! This is interesting! I'll have to try it! Are you able to make some more changes in the BIOS? 😜

That's pretty much my level of messing with bios, I also unhidden some not important settings, unlucky I do not know to do more.
If you are willing you could try the performance with the new bios to check if anything change, it would be interesting!

VooDooMan wrote on 2021-04-08, 07:39:

That is not good... Were you able to bring it back to life?

I sent my motherboard to a user which is going to fully recap it, I'm waiting for the response, it is in his hands already.

Reply 18 of 42, by VooDooMan

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Nemo1985 wrote on 2021-04-08, 09:29:

I sent my motherboard to a user which is going to fully recap it, I'm waiting for the response, it is in his hands already.

Ok, I hope you will get it back fast so that you can have more fun with it 😀

I did myself some testing and comparisons with that „new” BIOS last weekend.
As you can see there aren’t many differences in options. I spotted only two:

1-bios-2.jpg
1-bios.jpg

It turned out that I also have the 1.3 REV. Here you can see the differences between them. At first glance the Rev. 1.6 is smaller. They use different BIOSes and some of the caps are in different places but the rest seems pretty the same.

0-p-ytki.jpg

I tried to test REV 1.3 with that “new” BIOS but the results were very poor... Shortly speaking REV 1.3 simply sucks 😀 Forget about Tualatins with that REV, don’t even try to overclock anything there... All you can do on that platform is install Coppermine CPUs. I tried one Tualatin Celeron 1000 MHz at 100 MHZ FSB but the system won’t start... At FSB 66 MHz I was able to enter Windows and do some testing. There is almost no performance gain between the old and new BIOS. It is not possible to overclock anything there... it just won’t work, at least with the CPUs that I used.

2-old-bios.jpg

I also tried that “new” BIOS on REV 1.6. I've even set some new records, but that is probably thanks to expermienting with different RAMs, but still the gain is very small.

3-133-Tualartin-10239-new-record-1gb-ram-goodram.jpg
3-150-Tualatin-10898-record-OC-150-mhz-ram-goodram.jpg

That BIOS provieded by “Nemo1985” hasn’t helped me in achieving anything new... I was hoping that it would improve overclocking but none of that happened.
- Still at 150 MHz with Tutaltins everything works just fine at timings 2,5-2-2-5/6 but when I set tRAS to 2 it is unstable (I had to disable the "nature" test in order to complete the 3D mark without a freeze)

4-150-2-2-2-6.jpg

- At 166 MHz, Tualatins with 512kb won’t run (the computer starts but it won’t let me log into Windows – lots of mistakes during the RAM test)

- At 166 MHz, Tualatins with 256kb will work but unstable (I was able to run 3D Mark 1999 only)

x-tual-166-mark-99-1-gb.jpg

-AT 166 MHz with Coppermines at 2,5-2-2-5/6 timings everything just works perfectly 😀

x-166-coppermine-1-gb-goodram.jpg

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Reply 19 of 42, by Nemo1985

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I'm having such bad luck with hardware, well maybe life in general, nowadays.
The motherboard came back recapped an (apparently) fixed.
I didn't try with the installed cpu and memory (P3 866 and 128x2 ddr), I went ahead and change both cpu and ram, guess what? ---- on the debug card and no way to make it boot.
I took it off from the working bench, briefly tested another component and mounted back, this time it booted (with the original cpu and 128mb ddr), so the problem lies in the cpu or memory.
If I change them it goes nuts.
Next I swapped the ram to a bank of sdram, guess what? It stopped booting once again! I noticed that on the debug card it gives a reset signal every 5-10 seconds when it can boot.
Anyone else had issues with switching from ddr to sdr?