Hey, I'm hoping someone here can give me some insight on my problem.
Before I start, here's a rundown of the system:

OS: WinXP Home SP2
CPU: AMD Athlon XP 2000+
Motherboard: ECS K7S5A
Chipset: SiS 735
BIOS: AMI
System Memory: 1024 MB DDR SDRAM

A few weeks ago I booted one of my machines and saw a message during boot that stated that there was an error with the CMOS settings and that default settings had been loaded. I noticed that the motherboard recognized my processor as an AMD at 1250 MHz, rather than the full frequency of the 2000+. So, I went to my BIOS settings and changed the front-side bus and DRAM frequency to 133 Mhz (the default is 100). This time the board recognizes the processor as an AMD Athlon XP 2000+ (as it should). However, Windows will not load. The system reaches the Windows 'loading' screen and after the screen disappears, the monitor turns black and Windows does not load. At this point I have to manually shut down the system. I have tried the Knoppix and Ubuntu live cd's and they don't load either.
If I leave the front side bus and DRAM settings at 100 MHz the system works fine, but it only recognizes my processor speed to be 1.2 GHz, which is wrong.

Before the CMOS error, this machine ran with 133 MHz settings at the full XP 2000+ rate. Can someone explain to me why the machine will not properly load the OS and how to fix it? Thanks for your help!

The numbers AMD put against their processors doesn't relate to the clock speed - it relates to the equivalent speed of a Pentium 4. An XP 2000+ will run at about 1200MHz, but because they work differently to a P4, AMD reckon that, at that speed, its equivalent to a 2GHz P4. also, be VERY careful when telling your 1.2GHz chip to run at 2GHz - you could very easily wreck it. Hope that helps.

I was under the impression that the XP 2000+ runs at 1.67 GHz. Even then, when the FSB is set to 100 MHz the motherboard doesn't even detect the processor as an XP 2000+, it just says AMD at 1250 MHz. When the FSB is set to 133, the processor is detected as an AMD Athlon XP 2000+.

You are running WinXP and your date and time are now wrong, unless you reset them. XP is picky about things like that, plus when you booted with the default settings @100FSB WinXP saw changes in your system hardware which MAY be causing the problem. I can't recall if there are any options in your BIOS for memory timing. If so, set to auto. Check date, time, disable any onboard hardware not being used and boot to safe mode. You may need to perform a system restore to a point prior to this problem. Also you should change the MBoard battery. You are correct as far as the BIOS settings for the memory and CPU. If Knoppix doesn't load, the boot order may be wrong. If not then you may have had a hardware failure. If you have more than one stick of RAM, try removing all but one and rotate them.

Hi OtheHill,

I reset the date/time in the BIOS settings after the default settings were loaded. I have 2 512 PC2100 sticks and I tried what you said, kept one in at a time, but to no avail. Do you happen to have any more suggestions?

Try entering the BIOS and finding a setting called "reset configuration data". Enable this for one boot cycle. This will allow the system to reallocate the system resources. If you have a dualhead video card, be sure the monitor is connected to the primary port. Did you attempt booting into safe mode by tapping F8 at startup. One other thing, watch the POST screens at startup to verify the hardware is being ititiated, especially the boot drive. All drives should be identified by model. If they aren't, check the configuration in the BIOS.

OtheHill,

I did try Safe Mode before, and it worked. I'm almost certain that the boot drive is loading because it shows the hard drive and cd-roms detected on startup. Also, the Windows 'loading' screen is shown, but as soon as the screen disappears and the Windows desktop should be loaded, the screen goes black and nothing can be done but to manually restart the machine. It only does this when the FSB and DRAM settings are 133 MHz.

Try the Reset option.

I've checked all the accessible settings that can be changed in the AMIBIOS utility, but I was unable to find anything that seemed to resemble the 'reset configuration settings' option. Is there anything else I can do or try?

OK

I have a ver. 1 of this MBoard so the BIOS MAY be different. Below I will list some of what I feel may be key settings.

STANDARD CMOS
Set date, time, Fdrive
Set all channels to AUTO

ADVANCED SETUP
Set desired boot order
floppy swap = disabled
floppy seek = disabled
password check = setup
L1/L2 Cache = enabled
System BIOS Ca = enabled
Timing setting = Normal
Latency = SPD
Auto detect dimm/PCI = enable
spread spectrum = disable

POWER MANAGEMENT
ACPI aware OS = yes
power management = disabled

PCI/ PnPlay setup
PnPlay Aware OS = yes
Primary graphics = AGP
4X
Allocate IRQ = yes

LOAD OPTIMAL SETTINGS = yes
these are conserative settings

LOAD BEST PERFORMANCE = yes if
system will run

FEATURES SETUP
disable any hardware not used

CPU PnP SETUP
This page should be done automatically if you set Auto detect on the advanced page.

Hello again, I hate to keep bugging you but this problem is really disturbing me. I just can't understand how the system goes from working fine with FSB/DRAM 133/133 to not loading the Windows desktop after I got the CMOS error message. Once I make it 100/100 the system works perfect, but if I have it at 133/133, the Window's loading screen comes up, finishes loading, then when the system should be loading the Windows desktop the screen just stays black and doesn't not display the Welcome screen. I tried the BIOS settings you recommended. I have the AMIBIOS v. 1.21.11 setup utility, here are the settings I have right now:

Standard CMOS Setup: everything is fine here

Advanced Setup:
Quick Boot - Enabled
Boot devices are correctly configured
Try other boot devices - Yes
SMART for Hard Disks - Enabled
Bootup Num-Lock - On
FDrive Swap/Seek - Disabled
Password Check - Setup
Boot to OS/2 > 64 MB - No
L1/L2 Cache - Enabled
Graphic Win Size - 64 M
DRAM Timing - Normal
CAS Lat - SPD
RAS Active - 6T
RAS Precharge - 4T
Auto Detect DIMM/PCI Clk - Enabled
CLK GEN Spread - Disabled
DOS Flat Mode - Disabled
Dram Driver Slew Rating - Normal
S2K I/O Compensation - Disabled

Power Management Setup:

ACPI Aware O/S - Yes
Power Management - Disabled
PowerOn by LAN/Ring - Disabled
RTC Alarm Power On - Disabled
Keyboard PowerOn Function - Disabled

PCI / Plug and Play Setup:

Plug and Play Aware O/S - Yes
AGP 4X Control - Enable
Primary Graphics Adapter - AGP
Allocate IRQ - Yes
PCI IDE BusMaster - Disabled

Features Setup:

OnBoard FDC - Enabled
Other hardware setup

CPU PnP Setup:

CPU Speed - 100/100 MHz

Is it possible that my processor is failing?

Your Advanced settings look good.
You should enable PCI IDE Busmastering in the PnP screen.
Something that I was thinking about is this. Do you know the history of the CPU. There used to be a method to change the processor settings by connecting the traces using a pencil. The graphite in the pencil lead would act like a wire and it did work. The graphite could eventually work its way off and then the chip would revert back. I am not sure if this processor was one that could be changed in this way of not. There is a program called CPUID that should tell you what procesor you actually have. If this is an authentic 2000 then maybe there is something wrong with it. The other possibility is the RAM. You could try manually setting the FSB to 133/100. This may allow the processor to run at default if the RAM is crapping out. You could also try running a memory testing program on the RAM. RAM could hold you back. You definately have a strange problem. The dey here may be the original CMOS error you received. This is a common error with a failed battery but you haven't said anything about the battery. If the battery isn't bad, then what generated the error. BTW, from the looks of your BIOS list I think you have one of the later versions of that MB. Do you have USB 2.0? That was the latest version. You might want to look in Device manager in Windows to see if all is well there. When bootin to the BIOS or to safe mode you graphics display defaults to Std. VGA. When booting into standard mode Windows the display will then engage the appropriate drivers. You could try updating the graphic drivers. These are more guesses than anything. A couple of other hardware items that could possibly cause you problem could be a failing power supply or a flakey graphics card. I tend to think as you do that this may be to do with the processor. The strange thing is that if the BIOS IS automatically identifying the chip correctly then it probably is really a 2000. keep me posted.

Yes, i'm quite certain it is a real XP 2000 processor, it's codename was Thoroughbred. The system has a Sapphire Radeon 9800 128 MB graphics board and it has the newest drivers from ATI installed. As for USB, I believe it has USB 1.1, I'm pretty certain it's not 2.0. As for the graphics card issues, I really didn't bring that up because I thought it could be ruled out. If the system boots fine with 100/100 then I thought the graphic card drivers were not the culprit. As for changing the settings to 133/100, my BIOS will only let me choose from 100/100, 100/133, or 133/133 unfortunately. How do I really tell if the battery on the board might be the problem? Additionally, how can I determine if the PSU is beginning to fail? I've asked a few other people about my problem and they also suggested that the PSU might be failing, or even the capacitors on my motherboard might be at fault. I'm beginning to feel like I've exhausted all ideas. :-/

You can see if the capacitors are bad. They are upright cylindrical acomponents scattered about the MB. Look for bulging tops or leaking oily residue at the base. I don't think that is the problem. You could try cutting down on the power comsumption temporarily by unplugging extra case fans and maybe even restoring the old video card, if you have it still. This would simply be a test to see if the PSU is weak. The processor does draw more current at 133. Check the capacitors.

ok, i just wanted to provide a brief update of what I've done. I checked the capacitors and everything seems to be alright there. Also, I took down the specs of my PSU, they are:

Manufacturer: EVA Electronics Co.
Model: EB-350P (i assume that means its a 350W)
max values:
+3.3 V 20 A
+12 V 10 A
-12 V .5 A
+5 V 30 A
-5 V .5 A

I checked the readings of the PSU with my BIOS (AMIBIOS) hardware monitor and they are the following:

Vcore: 1.584 V
Vcc2.5V: 2.480 V
Vcc3.3V: 3.184 V
Vcc5V: 5.026 V
+12V: 12.224 V
SB3V: 3.312 V
-12V: -12.295 V
SB5V: 4.919 V
VBAT: 3.344 V

Now, I don't have that much experience with computer PSUs, but from my experience with electronics it seems to me that the +3.3V value of 3.184 volts is low.

Also, another thing that I neglected to mention is that when i have 133/133 setup, it's almost impossible to boot my machine. I turn the power on, the fans run and the cd drives are powered, but the single beep never occurs (memcheck). I've found that if I unplug the PSU from the surge protector and plug it back in, I can then boot the machine. It's a real hassle. However, when 100/100 is setup, the machine boots without a problem almost everytime the system is cold-booted or restarted. Maybe this information will help us determine if the PSU can be ruled out, or if it should be further investigated. Also, I checked the ATX connector and it seems to be firmly seated.