K7S5A: One Minor Problem To Be Aware Of

[Jerry Jones]

It seems Rev. 4 and higher boards (Elite Group K7S5A) do, indeed, have troubles with 1.4gHz AMD Athlon Thunderbird processors at 133/133 as explained by the following PDF file:

http://prohardver.index.hu/download/ecs/k7s5a_corruption_fix.pdf

1. Rev. 4 and higher boards do not correctly program the AMD bus driver impedance on the fastest Thunderbird CPUs.

(ECS - according to the PDF above - has changed the rev. 4 boards and higher to program 60 oHms to the CPU while the AMD revision guide from April 2001 calls for 40 oHms. Athlon MP and Athlon XP processors can work at either 40 or 60 at 133/133 while the Thunderbirds cannot.)

2. The problem has been *fixed* on the CBMB04 boards (almost identical to the K7S5A) sold at

http://www.samsclub.com or http://www.cpubuilders.com

3. The problem does not affect AMD Athlon MP/XP processors

4. Rev. 4 and higher boards can be "fixed" to work with Athlon 1.4s, according to the PDF above, by way of a complicated soldering modification (which I have no intention of trying)

Personal experience:

1. Flashed to the latest bios
2. EG465P-VE power supply (431 watts)

http://www.enermax.com.tw/products/eg-365p-ve.htm#s

3. Corsair PC2100 DDR
4. Windows 2000 SP2 + all sound/video driver updates
5. 1.4gHz Athlon Thunderbird

No problems with cold boots or any other booting issue.

Computer seems to run fine at 133/133 until I attempt to encode large .avi files to MPEG-2 video file format using Ligos encoder.

First thought I had fixed the problem by setting memory timing to
"SAFE" instead of "NORMAL" as I was able to encode more than 2 hours without a system restart, but later the system restarted when I attempt to encode a larger file.

Succeeded in encoding more than four hours of video (twice) at the 100/100 setting. No restarts whatsoever. Completely stable operation.

So the problem is at the 133/133 setting.

Now buying a replacement processor: XP2000+.

Other than the problems with the Thunderbirds at 133/133 setting, this board runs great.

Will report back on results of XP2000+ test.

Jerry Jones

[GNEP]

Do you think that this could be related to what I am seeing on another ECS board?

I have a K7AMA and a 1.4GHz Thunderbird, with 2 sticks of 256Mb DDR RAM (which run fine in another machine at 266)

The problem is this: no matter what BIOS settings/jumpers I play around with, the board refuses to recognise the clock multiplier as being anything other than 11.5x - which forces me to run the FSB at 100 (ie DDR at 200), giving a processor clock speed of 1150MHz.

Using jumpers to set the FSB to 133 gives a clock speed of 1529MHz, which can boot as far as the BIOS settings, but not into Windows (I do not want to start trying to cool it lots and running an "overclocked" (by mistake) system!)

At 100MHz FSB, I the system runs very stable, so I have been happy to leave it, and perhaps get a new motherboard when I feel the need for a bit more speed.

The multiplier should be 10.5x, which would give me the right clock speed at 133MHz.

I haven't tried the chip on another motherboard (not many friends have computers that can take an Athlon), and have searched the web for something similar, but to no avail.

Any suggestions? The K7AMA (AFAIK) would not allow me to change the multiplier even if I did the pencil trick on the Athlon to unlock it.

I may be going completely wrong here, as the last time I fiddled with hardware in great detail was with a 386DX-40 (also an AMD believe it or not!) a good many years ago - it's been laptops in the interim...

cheers

gnep

[Jerry Jones]

I don't know.

What I do know stems from my experience with the K7S5A, which is truly a great value - but for the one problem with Thunderbird 1.4s (and only then with rev. 4 and higher boards).

Rev. 1 - 3 boards work fine with the Thunderbird 1.4.

The switch had to do with anticipating the needs of the Athlon XPs... apparently.

Jerry

[GNEP]

I too have heard good things about the K7S5A, although not so much about ECS in general. Not many people are using th K7AMA board as far as I can tell, so I might just try fiddling about with it some more.

Thanks anyway,

gnep

[Marshmallowman]

1.4G athlons are factory unlocked there multipliers can be changed if your motherboard supports it.

All I can suggest is a bios update and/or reseating the CPU..perhaps the BFID pins are not contacting properly?

PS I run my 1.4 at 1496 136x11, it is not quite stable at 11.5*133
...

[GNEP]

Thanks - I will have a go at re-seating it this weekend. The K7AMA unfortunately doesn't allow any o'c-ing. In fact, the BIOS seems to have even less tweakable options than my P133 laptop!

gnep

[Jerry Jones]

Well, I just installed my AMD Athlon XP2000+ on my rev. 4 K7S5A and it runs GREAT!

My Athlon 1.4gHz Thunderbird refused to be stable on the board at 133/133.

The 1.4gHz Thunderbird does, indeed, have issues with the rev. 4 boards, in my opinion.

Thanks to "Mr. Athlon"...

http://www.geocities.com/mrathlon2000/zp.html

"Mr. Athlon" discovered the "Zp, Zn" issue with rev. 4 boards...

Thanks to him, I learned my true options were to either:

1. perform a solder fix on the board so that it would work with the 1.4gHz Thunderbird: http://prohardver.index.hu/download/...uption_fix.pdf

or

2. simply upgrade the processor to an XP.

I did so tonight.

I am delighted to report Mr. Athlon's suggestion has worked beautifully.

The XP2000+ is running happily at 133/133.

I've run the Memtest - 86 with none of the errors that showed up with the 1.4gHz Athlon Thunderbird.

(My 1.4 Thunderbird refused to be stable at the 133/133 bios setting due to the ZP resistor values having been changed on rev. 4 boards in anticipation of the XP processors.)

For details, about Mr. Athlon's findings...

...read this:

http://www.geocities.com/mrathlon2000/

I'm very, very glad I did *NOT* follow the so-called "advice" given on the heavily-censored OC Workbench forum where any mention of Mr. Athlon and his fix is removed from public view.

Had I listened to the prevailing view of the OC Workbench crowd, I would have wasted in the neighborhood of $250 as the prevailing opinion on that forum is that Athlon 1.4gHz problems are mostly caused by inadequate power supplies or bad ram. Even though I explained I was using an Enermax 431 watt power supply and my CPU temperatures were low (Swiftech heatsink) and I was using high quality Corsair DDR PC2100 memory, the individuals on the OC WorkBench forum kept suggesting that I had either a "heat" problem or a "power" problem.

I'm glad I did not listen to them. Instead, I listened to Mr. Athlon and saved $250 and I have a rock-solid-stable PC.

To the folks at OC Workbench: Due to your practice of censoring posts related to this fix, I do not plan to ever visit your Web site again unless you make a sincere and contrite public apology.

Meanwhile, my heartfelt thanks to Mr. Athlon.

My K7S5A is performing flawlessly for video editing and MPEG-2 encoding!

Jerry Jones

http://www.jonesgroup.net

[Jerry Jones]

Encoded THREE HOURS of MPEG-2 video last night using the XP2000+ and the Elite Group rev. 4 K7S5A.

ROCK SOLID STABLE.

I also changed the memory timing in the bios from "normal" to "ultra" and ran the Memtest 86... ROCK SOLID STABLE.

This is a great board for $70 if one is simply careful to match one's processor the specific revision number.

Jerry Jones