Can low CMOS battery affect stability?

[UCLAPat]

Hi. I was wondering if a low CMOS battery can affect system stability.

I just recently got a motherboard (ECS K7S5A) to go with my new AMD Athlon XP 2100+. I've reset the CMOS via the jumper and I still get two separate error messages for the CMOS.

I have a system instability problem that's related to the system, motherboard or video card. 3DMark2001SE crashes before completion (within 5 minutes). I also tried a quickie game (High Heat Baseball 2001). I've swapped sound cards (from my trusty SB Live Value to the onboard C-Media AC97 audio) which didn't help. I've disabled ACPI and power management in the BIOS. Anyway, I get a complete hardlock after a couple minutes of play. I am not overclocking anything.

I have the latest drivers for everything (AGP, video, sound, USB, etc.). I've made a ton of adjustments in the BIOS (though they apparently aren't kept properly because of the battery).

The memory is new. The video card is the BFG Asylum Geforce4 Ti4200 128MB card and is new (Best Buy deal!). The CPU and motherboard are also new. It's a fresh installation of the OS (WinME and WinXP, separate Ghost images, not a dual-boot config).

If a new CMOS battery doesn't solve the problem (which should come on Monday, according to NewEgg tech support), I'll get the final new thing to complete my system: a new case+PSU. Maybe my PSU is getting flaky. Who knows.

If anyone recognizes me, this is the guy who replaced the TBird 800 with V5 for this new system.

 

[osage]

There has been some history with some of the K7S5As and not holding the CMOS. Replace the battery is prob a good move, also check to be sure you are leaving the jumper on the corect pins, so,e of the early boards had it marked wrong in the manual. Some ppl have also reported this board as being picky about a good clean PSU, so if you PSU is old,low wattage, or of unknown quality a upgrade may well be in order. 500W is not nessasary, it is more important to use a good quality PSU, PowerMan has a good history with these boards for for a PSU that is not too expensive.

If the problems continue search this forum, many good theads relating to this mobo.

 

[cp668]

I read somewhere (Newegg feedback?) a reseller replaces all K7S5A CMOS battery when he received the board, always so.

I also read somewhere (OCWorkBench?) that people learned from ECS tech support "suggesting" PSU for this MB better to have 28 amp on 3.3v line! My 350W PSU does not even come close!

Hope this help.

 

[KF]

Since the settings in CMOS are used to set up the mobo chipset, and a CMOS error indicates the settings have errors, yes it could cause instability.

From reading many posts on this K7S5A mobo, I am persuaded this mobo has contact problems for every possible contact. I think it is likely the CMOS problem is a contact problem with the battery contacts. Contact problems are cured 90% of the time by simply removing and inserting. But sometimes they are persistant.

The "picky" power supply characteristic could also be a contact problem (the PS connector). Cheap powers supplies have cheap everything, including cheap ATX connectors. One of the characteristics of a contact problem is once you have changed something to get it to work, you put everything back the way it was to start with, and it works too.

Sometimes I have long streak of good luck with no contact problems, and I start thinking it is a thing of the past.

Here is what happened to me recently. I fired up an old (5 years) mobo in preparation for some changes I had in mind. It worked perfectly, like it always has. So I was set to start making changes. I put a larger memory DIMM in, and a NIC card I that I used to use with it. It refused to boot ( black screen- 3 beeps.) I pulled the card and memory out and did the routine reinsertions. No boot. I restored the computer to its original configuration. No Boot. ??? A different video card. Boots fine. So the video card is all of sudden bad? The "bad" video card had two memory chips and a ROM that were in sockets, so I took them out and put them back in (reseating). The first boot did not work, but the second did. I figured I had fixed the video card contact problems. I did some torture tests under XP. Everything was fine. I then attempt a reboot, and I'm back to a black screen - three beeps, and the same no matter how many times I retry. So I do the routine with reseating the chips on the video card again, with 6 reseats to make sure the corrosion is burnished off. That cured the problem. I put in the memory and NIC, and the computer has been working for a couple weeks. This is what can happen to you with contact problems.

A contact problem can appear to fix itself. You just flex the mobo a bit and that is enough movement to get something to make contact. Or it can be temperature related. The thermal expansion can cause enough movement to intermittently get or remove contact. I had a problem like this in a power supply connector once, and the only way I knew it was that the plastic shell ultimately deformed and swelled. Since that pointed me to the problem, then I could feel that that one contact would get hot after say 15 minutes. If it had made really good contact, it would not have gotten hot.

 

[UCLAPat]

Hi. Thanks, everyone, for your help and advice! Very much appreciated. The online store (NewEgg) is already shipping out a new CMOS battery for me.

As for the power supply, I will be getting a new one. After reading the FiringSquad article about PSU's, 3.3, 5, 12V stuff, I found out that my PSU is borderline useful, especially with all the stuff I have in my system.

I saw this one online for really cheap. What do you guys think?

http://www.dealsonic.com/ag40pen4atxs.html

A+ GPB 400W Pentium 4 ATX Switching Dual Fan Power Supply, Retail Package
Price: $32

AC INPUT: 115/230 Vac~ 14/7A 60/50Hz
DC OUTPUT :

COLOR BROWN RED WHITE YELLOW BLUE PURPLE BLACK GREEN ORANGE
DC +3.3V +5V -5V 12V -12V +5V-SB COM PS-ON PW-OK
OUTPUT 20A 40A 0.5A 17A 1.0A 2.0A RETURN REMOTE P.G.
+3.3V and +5V max Output 240W, Peak Surge Max Output 436W

 

[mindless1]

Low CMOS battery will not cause instability.

If the CMOS battery were nonfunctional the defaults would be used, and if the defaults are REALLY that instable, it's time to throw the board in the trash, the manufacturer doesn't know WTF they are doing.

Forget about getting some "really cheap" PSU, this is probably the problem in the first place. A good 300W PSU is better to have than a cheap 400W.

 

[stevewm]

Concerning CMOS problems:

Go into the Hardware Monitor screen in the BIOS. What voltage is reported for VBAT? This is your CMOS battery voltage. It should be 3v or higher. If its any lower than 3v then the battery is definately dead. However a dead CMOS battery would not cause random hardlocks. Unfortunately some k7s5a's did ship with dead/bad CMOS batteries. If a new battery does not solve the CMOS problems then don't waste your time trouble shooting any futher, RMA the board.



Concerning Lockups:

This board demands a very good power supply.

Your power supply must provide no less than 28Amps on the 3.3v line, 20A on the 5v, and 1A on the 5v standby line. Go below these requirements and YOU WILL have problems! The power supply you posted does not meet the 3.3v requirement of 28A or more.

How much and what type of RAM do you have? What about memory timings? I was going to suggest setting your memory timings to "Safe" or "Normal, but since your CMOS settings do not save....... If your using SDR RAM this board is known to need good quality "up to spec" SDR RAM modules, otherwise problems occur.

ACPI should definately be enabled in the BIOS. If you installed the OS with ACPI enabled and then disabled it in the BIOS that could possibly cause problems with WinXP....

 

[UCLAPat]

Wow! I didn't know it was so hard to power this puppy!

Here's the power supply I've settled on.

www.newegg.com/app/viewproduct.asp?DEPA=&submit=Go&description=AL-B450EATX

http://www.newegg.com/app/viewproduct.asp?DEPA=&submit=Go&description=AL-B450EATX

MODEL: ALLIED AL-B450EATX
MAX 450W
+3.3V/28A
+5V/50A
+12v/18A

I have 512MB of SDR memory. It is Crucial CAS2 and I've used it since I built my Athlon 800TB system.
The memory settings were set to Normal.

I initially had ACPI installed (in BIOS and WinXP Pro OS). When XP was unstable, I turned it off in the BIOS.

Thanks for all the help everyone! This board is the best and everyone's really bright and helpful.