Question Oh No! Not another no POST beep or video display question.

[LooseCannon496]

Hello everybody and thanks in advance for comments. But this question is different because it's not a brand new build, it's an antique computer. LOL "How old is it?" you ask. Why, the MOBO box says "It's Windows 7 ready" but the manual talks about using Vista .

Anyway, my problem started Thursday night when I broke computer usage Rule #1 -no eating/drinking at your workstation. (I got jelly all over the mouse, ok). After cleaning my hands, I used W10 "shut down" instead of sleep for the first time in months. (possible cause?), then removed and cleaned USB mouse. When I went to plug it back in the same port I needed to lift & tilt the case up on it's front edge to see the port (possible cause #2?).
Hit the power button. DVD player chattered like normal, case fans sped up and lit up, CPU fan came on, GPU fan came on-but no POST beep or display.

Components
Case CoolerMaster 932 HAF
PSU CoolerMaster RS-650-ACAA-A1
MOBO ASUS M4A785TD-V EVO/U3S6
CPU AMD Phenom II 945 Black
RAM 4 GSkills Ripsaws 2 GB DDR3 (2 installed at first build, 2 added in 2018)
Most of those components were assembled in Sept 2010. Which means the PSU is hardwired no plug-in connections. The MOBO only has one diagnostic light (SB_PWR onboard power) and it lights up.

The 2 extra RAM, the Samsung SSD, and EVGA GeForce GTX1050Ti were added in 2018. The free Windows 10 upgrade was done in January 2023.

After removing the side cover I found no dead insects inside, the working power light, and only a loose connection to the front panel audio. Also, moved the display cable from GPU to MOBO connection-no change.

There's a jumper for resetting the CMOS RTC RAM (I think the battery is original) but I'm a little scared about trying that. (Would it work with a dead battery?) Should I try testing the voltage where the 24 wire cable plugs into the MOBO? (Where can I get a wiring diagram?) If the GPU or SSD were bad wouldn't I get the POST beep?

Please post any ideas, suggestions, or things I might be missing.

 

[Misgar]

Change the CR2032 battery. I've several computers that won't POST with a dead flat battery. A new battery should be about 3.30V.

I change batteries when they drop below 2.90V. Below 2.00V and you'll probably lose all the BIOS settings.

If you're lucky, the computer will start up at least to the BIOS splash screen when you fit a new battery. You'll probably have to set the boot drive in the BIOS.

I have a Phenom 955 and a 965 in my collection running XP, 7 and Windows 10.

 

[LooseCannon496]

Change the CR2032 battery. I've several computers that won't POST with a dead flat battery. A new battery should be about 3.30V.

I change batteries when they drop below 2.90V. Below 2.00V and you'll probably lose all the BIOS settings.

If you're lucky, the computer will start up at least to the BIOS splash screen when you fit a new battery. You'll probably have to set the boot drive in the BIOS.

I have a Phenom 955 and a 965 in my collection running XP, 7 and Windows 10.

Thanks Misgar, the problem does seem to be related to the CMOS battery. Sunday morning I found a new (still in package) CR2032 at home so I took it and a voltmeter over to the office. I'm guessing that battery at about 6 years old as it was one of two bought for a smartkey fob for a car that was sold 4 years ago it read 3.15 volts when tested. (old battery tested at 3.2V ???)

But it worked or it did when first installed with the desktop laying on it's side. The computer posted and I reset the BIOS time and it shut down normally. Went and did some other stuff and about two hours later put the case back on the floor (normal upright position), finished connecting all cables and tried to do some work on the desktop.

Tried is the word because it failed to POST again! Checked Walmart.com for inventory at nearest store but they had none in stock. So this morning I went by Home Depot ,picked up a new one, installed it, and again no POST. Even laid case over on it's side again and removed cables but nothing. Just fans, lights, and DVD chatter.

Could that circuit on MOBO be bad?

 

[Misgar]

3.15V is virtually fully charged. Keep this battery as a spare.

Try booting with just one DIMM installed. It can sometimes wake up a "stuck" BIOS.

Do you have another PSU you can try? The electrolytics in an old PSU may have dried out or burst.

It's a process of slowly changing components until you find the faulty part. I'm lucky because I have three working motherboards with two 955s and a 965.

 

[LooseCannon496]

3.15V is virtually fully charged. Keep this battery as a spare.

Try booting with just one DIMM installed. It can sometimes wake up a "stuck" BIOS.

Do you have another PSU you can try? The electrolytics in an old PSU may have dried out or burst.

It's a process of slowly changing components until you find the faulty part. I'm lucky because I have three working motherboards with two 955s and a 965.

Sorry for the delay in getting back here. Replacing the PSU was the solution to my problem. On Tuesday I found an article on both the paper clip jumper and using a multimeter to test the 24 pin connector. Most voltages were correct except for the green wire which never read over 6 volts. So I ordered a new PSU from Amazon and got it later that day.

Took it to the office on Wed. and that's where the fun really begins. I bought the Apevia Premier 650W 80+Gold certified because it had 86% 4&5 star reviews. The things I had issues with are:
1. The manual is a bad joke with 4 tiny pictures showing the cables attached as "installation instructions" and their website is worse.
2. Other online reviews show people had a very low opinion of their older products. (I'll hope the newer PSU is better).
3. Didn't notice in the pictures that all wiring was black. Something that only appeals to idiots.
4. 20+4 pin mobo connector cable, 8 pin and a 4+4 pin CPU connector cable, a Molex, sata, and floppy drive connector cable (Never had a floppy since 2010).
5. That cable was too short to use with my SSD, Dvd, and front panel connections so I had to use one of the other cables, too. (A second with 3 Molex connections).

But it works, it only cost some Discover points (free), and it's made in Taiwan not China. (I try to no longer buy products made under the CCP). Three days working and when I need a laugh I can walk around my desk, get down on the floor and watch the stupid light show it puts out. RGB FTW!!

Is there a way to mark this thread solved?