EPoX EP-8RDA+ - Non Working Condition

[davmax]

Re: EPoX EP-8RDA+ - Non Working Condition

From my experience you do not need a 24 to 20 adapter for older boards. The extra 4 pins supply th extra leads to supply the heavier current requirement of later boards.

It does depend on components, often the 24 will plug into the 20 making sure the overhang is at the correct end.

[gdement]

Re: EPoX EP-8RDA+ - Non Working Condition

Hmmmmm.......how much current does that circuit need?

I'll have to use an adapter to connect the 24-pin power supply to the 20-pin board, so whats wrong with splicing in one of those '7805' voltage regulators?

I think they are rated at 1 amp.
.

Not sure how much current you'd need, but I think the most common PSU problem for Epox boards isn't just the amps, it's the joint regulation that some power supplies use. Since the load isn't balanced, the PSU allows one rail to sag (even if it isn't overloaded), because some other rail is high by an offsetting amount.

Unbalanced PSU load is a problem with the EP-8K7A, and I just recently found a similar design trait on an older Slot-1 EP-BX3 board. On that BX3, onboard 3.3 is regulated from the 5V input, and the PSU 3.3 input pins are totally open. So a 3.3+5V joint regulating PSU would probably suck at running it.

I've read recommendations for 30Amps on 5V on 8K7A's, but they seemed to run okay for me on a 20Amp HiPro. 5V did sag a bit depending on load, but usually not enough to matter. So if this were an 8K7A, I guess I'd be aiming at 25 quality amps if it's not a heavy setup. The biggest killer is if the PSU doesn't regulate 5V independently, then it's just going to sit and watch while 5V drops like a rock.

Not experienced with using 7805's, but I think they need a heatsink.


Another possibility is that the installed BIOS doesn't like your CPU. I had to flash the 8K7A's before they'd boot a Thoroughbred. Also, some boards had a goofy custom BIOS on them that was fixed to 133FSB, so my 100FSB TBird couldn't boot either (the board jumper is deceiving, it doesn't really control FSB, just the ratios). Safest starting point is probably a 133FSB Palomino, if you have one. I'm just extrapolating from the 8K7A though, I don't know what the quirks are on the 8RDA.

[gdement]

Re: EPoX EP-8RDA+ - Non Working Condition

From my experience you do not need a 24 to 20 adapter for older boards. The extra 4 pins supply th extra leads to supply the heavier current requirement of later boards.

It does depend on components, often the 24 will plug into the 20 making sure the overhang is at the correct end.

From the picture of that board, it looks like an inductor will be in the way.

[gastorgrab]

Re: EPoX EP-8RDA+ - Non Working Condition



We have POST!


But i don't know what made the difference; the remaining row of Sanyos that i replaced, or the power supply.

I currently have it running in the PC Health section of the Award BIOS to see if it remains stable. If all is well i'll load a mini OS to the IDE to CF disk and poceed with the proveout.

If it survives, i intend to try the original crappy power supply again. The power supply worked with other boards and im sure it isn't completely crap. It may just be that the power requirements for this board are 'special'. I'd like to know for sure.


Thanks Fellas.
.

[gastorgrab]

Re: EPoX EP-8RDA+ - Non Working Condition

It keeps freezing when i try ti intstall an OS, but still posts with the 'FF' code.

I hope it doesn't have a bad IDE controller.

I've used this IDE-to-CF disk adapter before without problems, and the DVD-Rom cable is brand-new...........

Maybe it's time to flash the bios to latest firmware.




I'd hate to think that i may have to use an actual hard disk drive to make this machine function. It sorta negates the idea of idea of using a slightly older board.
.

[davmax]

Re: EPoX EP-8RDA+ - Non Working Condition

How has this board gone now? The last post seemed to indicate a memory or hard drive problem. Does it pass memtest? From boot floppy or CD.

[gastorgrab]

Re: EPoX EP-8RDA+ - Non Working Condition

I'd flash the bios if i could be sure it wouldn't freeze up during the attempt. Of course, there shouldn't be any reason why a Thoroughbred core would confuse this board.

......and the southbridge gets pretty hot while it's runing.

This board never freezes while it's in 'Setup', it's only when it runs off of a hard drive or live-cd.

I have a floppy drive around here somewhere. I'll test it again to see if the machine locks up while running from a floppy.

Hmmmmmm.......
.

[gastorgrab]

Re: EPoX EP-8RDA+ - Non Working Condition

Another possibility is that the installed BIOS doesn't like your CPU. I had to flash the 8K7A's before they'd boot a Thoroughbred.

I need to read a little more thoroughly.
.

[gdement]

Re: EPoX EP-8RDA+ - Non Working Condition

I need to read a little more thoroughly.
.

Your symptoms are different from mine. In my case, a thoroughbred simply wouldn't boot until I flashed it first with a palomino. So I'm doubtful this is your issue, but maybe minimizing the load and dropping to 100mhz bus would make it more stable for a flash.

The "FSB" jumper, by the way, is a lie (assuming it's like the 8K7A). It doesn't control the FSB. It's actually a PCI ratio jumper. "133mhz"= 1/4 ratio, "100mhz" = 1/3 ratio. So if that setting doesn't jive with your FSB setting in the BIOS, then you'll get an overclocked PCI bus which could cause some pain. Make sure you've got your jumper in the 133 position, unless you've actually dropped it in the bios. The official Epox BIOS *should* detect this jumper and reconfigure itself, but all might not be as it seems:

On the POST screen, does your BIOS version show some company name in parenthesis? I can't remember what mine said there exactly, but I had some liquidated boards where the BIOS was a customized version. The onboard RAID was disabled, the FSB was locked at 133mhz, the RAM latencies were forced, and who knows what else.

If your board has a custom BIOS, then that could very well be causing trouble. Especially if your components don't live up to the games it's trying to pull.

***
[edit: I posted the above forgetting that you're on an 8RDA+, not an 8K7A+. I tried to revise it, but if I wrote something that doesn't make sense, that's probably why.]

[PCBONEZ]

Re: EPoX EP-8RDA+ - Non Working Condition

Does anyone know what the KQC brand is that was mentioned earlier in this thread?

[chipper]

Re: EPoX EP-8RDA+ - Non Working Condition

You definately have a nice sized board there. I have an EPOX EP8K9A2+ mobo ( the overclocker ). It can push 2800mhz at the outside with the 2700 chip.

If you don't have 1 , you might want to use a soldering gun to replace caps in tight spots. I've got 1 that has a built in light that goes on when it is triggered and it heats up so fast that you just pull the cap right off the board.

But : If you consider that any PCB is sensitive to heat at the solder points you might want to just squeeze the cap flat with pliers and go over the top with a small pair of sidecutters. Then leave the 2 original soldered leads on the board while you do an overlap solder with the new cap leads. This will make sure the mobo seat stays put and undamaged by heating or removing.

So what if the new cap has a 1/4" stand instead of being directly on top of the board. I usually won't reheat a solder point that is already (white) or had been heated too much somehow in the first place. I use the old style , hook it up and go method instead of risking losing the board contact.