I’d be tempted to get a post test card and see what that has to say.

Have you got a low power GPU you can try, something that doesn’t need any external power? Do you have another PSU you can test with also?

paradigital wrote on 2023-05-28, 19:33:

Have you got a low power GPU you can try, something that doesn’t need any external power? Do you have another PSU you can test with also?

I have an ATI/AMD 6570? in another system that's half-way to the e-waste pile (anyone feel like there's any value in a Dell Vostro 200 or 220 SFF?). Probably hasn't been touched in 7 years, but I should be able to pull it out if need be.

No spare PSU that I can think of, and I am not taking apart my functioning main desktop to steal its PSU.

Be bold, remove all ram and the video card. If anything else is ok then you should have the appropriate beeps present on the pc speaker (if connected correctly).

I would be most suspicious about the PSU.

I know I'm only a sample size of one, but I had the exact same PSU in a system from similar era to yours. Last year I pulled that system out of the closet and after running it for a little while it started to get flakey. Swapping the PSU out with a spare I had on hand fixed my problems.

danieljm wrote on 2023-05-28, 23:24:

I would be most suspicious about the PSU.

I know I'm only a sample size of one, but I had the exact same PSU in a system from similar era to yours. Last year I pulled that system out of the closet and after running it for a little while it started to get flakey. Swapping the PSU out with a spare I had on hand fixed my problems.

How flakey was yours? I'm actually starting to wonder if it's possible that my X-Fi card isn't actually dead but was seeming dead (being detected but drivers both Windows and Linux couldn't start up) due to power delivery issues.

I forgot to mention - I ordered a PSU tester that showed up today, so I will give that a shot as well.

That being said, it just seems odd that the 'new' GPU would fry the PSU, but I suppose going from a 1 6-pin connector to a 2 8-pin connector GPU might have pushed it over the edge somehow. And actually, one thing I just realized - I don't think I had it on for most of the week waiting for the new GPU, so I suppose it is possible that if I had tried to power it on with the 5770 the day the 7970 arrived, it would have failed to POST.

VivienM wrote on 2023-05-28, 18:11:

The 17-year-old SB X-Fi seemingly died after a few hours, okay, fine, so had to take that out, but everything was happy.

if you are good enough, or have friend with a soldering iron - replace the biggest capacitor near the DSP (main chip).

shevalier wrote on 2023-05-29, 02:57:

VivienM wrote on 2023-05-28, 18:11:

The 17-year-old SB X-Fi seemingly died after a few hours, okay, fine, so had to take that out, but everything was happy.

if you are good enough, or have friend with a soldering iron - replace the biggest capacitor near the DSP (main chip).

I have zero soldering skills and... the only friend with soldering skills I can think of lives over 1000km away. But at some point I probably should learn...

VivienM wrote on 2023-05-28, 23:29:

I forgot to mention - I ordered a PSU tester that showed up today, so I will give that a shot as well.

PSU tester showing healthy voltages, for better or worse...

I am almost tempted to pick up a new PSU before trying some of the other troubleshooting steps suggested here. Another 750W, probably... Corsair CX750M?

Try reinstall CPU, and start matherboard without RAM.
Just CPU, speaker and PSU.

VivienM wrote on 2023-05-28, 23:29:

How flakey was yours? I'm actually starting to wonder if it's possible that my X-Fi card isn't actually dead but was seeming dea […]
Show full quote

danieljm wrote on 2023-05-28, 23:24:

I would be most suspicious about the PSU.

I know I'm only a sample size of one, but I had the exact same PSU in a system from similar era to yours. Last year I pulled that system out of the closet and after running it for a little while it started to get flakey. Swapping the PSU out with a spare I had on hand fixed my problems.

How flakey was yours? I'm actually starting to wonder if it's possible that my X-Fi card isn't actually dead but was seeming dead (being detected but drivers both Windows and Linux couldn't start up) due to power delivery issues.

I forgot to mention - I ordered a PSU tester that showed up today, so I will give that a shot as well.

That being said, it just seems odd that the 'new' GPU would fry the PSU, but I suppose going from a 1 6-pin connector to a 2 8-pin connector GPU might have pushed it over the edge somehow. And actually, one thing I just realized - I don't think I had it on for most of the week waiting for the new GPU, so I suppose it is possible that if I had tried to power it on with the 5770 the day the 7970 arrived, it would have failed to POST.

It very quickly degraded over the course of a day or two. At first it was just some odd instability, then it wouldn't reboot properly needing a full power off/disconnect, and finally it wouldn't do anything.

I know it can be a real pain to diagnose these sorts of issues(especially if it is PSU related). It's easy to end up throwing money away trying to find what fixes the problem. I'd certainly try some of the other advice first, like trying to strip it down to the bare essentials to see if you can get it up and running. Maybe just keep it in the back of your mind for now that it could be a PSU problem.

shevalier and bogdanpaulb told You what to do! Leave only CPU and speaker on MBO, and You will know everything! If there is no sound from speaker than, You are sure to have faulty CPU or MBO (99% MBO, and 1% CPU according to my experience). After that, if You have sound (beeps), You can try anything else, until then, don't even bother with other components. Assuming that Your PSU is ok....

Well... tried taking the GPU out. No change - no POST, no beeps, no anything. Just the CPU fan. Haven't tried taking the RAM out, honestly I am inclined to think there is little point...

I suppose it's possible my brand new PC speaker is bad, though that seems unlikely. So... time to go to the computer store and pick up a new PSU?

PSU testers don´t help here, because they just measure the voltages without being a realistic load for the single PSU rails.
The tester will pretend the PSU is o.k. even while one or more voltages break down under regular load / operation.
These testers can only indicate if a voltage is missing or out of tolerance.
Always test a dodgy PSU by replacing it by a known good, preferable new, PSU.

Back from the computer store with a shiny new Corsair RM650x PSU. *sigh* I was planning to get something more value-minded, but... everything lower priced seemed to have dreadful reviews, so... (this project is really costing more than expected)

Fingers crossed this revives it...

... and, new PSU is in, with the 7970 and the RAM, no POST. Argh.

VivienM wrote on 2023-05-30, 03:34:

Haven't tried taking the RAM out, honestly I am inclined to think there is little point...

Inclined to think that based on what, exactly?

Bad RAM can have all kinds of bizarre symptoms, since the CPU keeps the stack there, among other critical information.

No RAM is a known situation, the BIOS has code to determine that no RAM is installed, and waggle the PC speaker to let you know.

Bad RAM though? All bets are off.

Powering without RAM is the best way to verify the CPU and motherboard have at least some signs of life.

SquallStrife wrote on 2023-06-02, 02:31:

Inclined to think that based on what, exactly? […]
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VivienM wrote on 2023-05-30, 03:34:

Haven't tried taking the RAM out, honestly I am inclined to think there is little point...

Inclined to think that based on what, exactly?

Bad RAM can have all kinds of bizarre symptoms, since the CPU keeps the stack there, among other critical information.

No RAM is a known situation, the BIOS has code to determine that no RAM is installed, and waggle the PC speaker to let you know.

Bad RAM though? All bets are off.

Powering without RAM is the best way to verify the CPU and motherboard have at least some signs of life.

I'm going to try that next, I think. The reason I thought there was little point is that it seemed odd to me that replacing a GPU (and taking half of this poorly-designed case apart in the process because I had a hard drive in the GPU's way) would somehow break/dislodge/etc RAM that had been happily in those slots for 13 years.

Probably more likely that I dislodged the CPU that had been in there... two?... weeks, I suppose... but... CPUs don't really dislodge themselves from LGA sockets, do they?

(I'm just stubborn enough to spend another few hours on this over the weekend... after that... well, I have a friend with an underused Ivy Bridge box, those run XP, don't they? So maybe I just make him an offer he can't refuse...)

Well, this is new, I turned it on again (without touching anything since my previous post)... now I am getting continuous beeping...

... and it only did it once. Back to completely dead now... but at least I guess I know I plugged in my PC squeaker okay and it works.

Well, I'll be damned... started listening to you guys, took out half the RAM... and now it POSTs?!?!? (or at least I have screen display and errors about the CMOS I wiped earlier)