Old PC for Arcade build, not sure of the problem

[CaptainAfro]

First off, sorry if this is the wrong category, please move it if it is.

Alright so a while ago I managed to score 2 arcade machines for $50. Quite a sweet deal, especially considering I'm throwing my grandpa's old pc in one of them. I bought some new (used old parts ) parts for it for cheap and got it running really well, considering. Then the mobo died. I bought another one to the same specs on Ebay and plugged it all in. No display, not even a POST, with the onboard port OR the graphics card. Motherboard boots up, fans go on but nothing else really. The mobo speaker got crushed somehow so I can't tell if it's beeping or not. I've tried it with practically all combinations of the old and new parts and still nothing. Here's the parts:

Mobo: Old - PC Chips M825 v7.1A
(http://www.baber.com/motherboards/pcchips/pcchips_socket_a/pcchips_m825lu_v7.1a.htm)
New -Gigabyte GA-7VM400M
(http://www.cpu-upgrade.com/mb-Gigabyte/GA-7VM400M%28Rev_1.x%29.html)
(http://www.gigabyte.com/products/product-page.aspx?pid=1670#sp)

Spoiler

http://i228.photobucket.com/albums/ee43/SonicBlaze425/Arcade%20Cabinets/Arcade%20Machine%20compie/080712_11182.jpg

CPU: Old - Amd Duron 1300
(http://www.cpu-world.com/CPUs/K7/AMD-Duron%201300%20-%20DHD1300AMT1B.html)
New - AMD Sempron 3300+
(http://www.cpu-world.com/CPUs/K7/AMD-Sempron%203300%2B%20-%20SDA3300DKV4E.html)

RAM: Old - 1x 256 MB ValuRAM KVR266X64C25
New - 1GB (2x 512 MB) DDR 266 PC2100 (ATP?) AG64L64C8SQB0S

GPU: nVidia Geforce FX 5900 XT 128MB AGP 8x

PSU: Maxpower PX-350W Ver. 2.03

I noticed on the old motherboard I connected the 20-pin wide connector, same as the new one, but the old one also connected a 4 pin connector. The new one doesn't have that 4 pin slot. Does that make a difference?

I tried to be as detailed as I could, but please tell me if you need more info.

Also I should mention the Power and "MSG" lights both stay solid when turned on, no blinking or anything.

 

[Bejusek]

I'd say that "new" motherboard bios is a old version.

Please notice that in first bios revision F1 only durons up to 1Ghz were supported http://faq.gigabyte.com/FileUpload/FAQ/1/744/file/tech_k7_slota.pdf

Looking at the bios history:
F4 - support for newer durons
F8 - support for semprons

That's why I guess, that both of your cpus are not recognized by MB and none of combinations worked.
Solution: try to get an older athlon / athlon xp / duron with sub 1000Mhz clock. You should be able to buy it for about $2

Then try to flash the bios to newest revision.

 

[CaptainAfro]

I'd say that "new" motherboard bios is a old version.

Please notice that in first bios revision F1 only durons up to 1Ghz were supported http://faq.gigabyte.com/FileUpload/FAQ/1/744/file/tech_k7_slota.pdf

Looking at the bios history:
F4 - support for newer durons
F8 - support for semprons

That's why I guess, that both of your cpus are not recognized by MB and none of combinations worked.
Solution: try to get an older athlon / athlon xp / duron with sub 1000Mhz clock. You should be able to buy it for about $2

Then try to flash the bios to newest revision.

I didn't even think about the BIOS, crap. That makes sense. Any suggestions on where to get old computer parts, besides Ebay?

 

[Bejusek]

Yeah, it makes sense, but mainboard may be damaged as well.

As for buying old cpu, I'd try auction services, garage sales, local ads etc.
Don't forget to ask your friends, maybe they have some old, no longer needed parts.

On ebay I found this http://www.ebay.com/itm/AMD-Duron-D750AUT1B-750-Mhz-Socket-A-462-/170831458841?pt=CPUs&hash=item27c6593219
its about $10 with shipping.

My $2 estimate was based on prices in my country and, looking at ebay prices, was too optimistic, sorry.

EDIT:
Another thought - try to get new speaker first, to check if board is signalling any errors.
I assume you have tried clearing the CMOS?

 

[CaptainAfro]

Yeah, it makes sense, but mainboard may be damaged as well.

As for buying old cpu, I'd try auction services, garage sales, local ads etc.
Don't forget to ask your friends, maybe they have some old, no longer needed parts.

On ebay I found this http://www.ebay.com/itm/AMD-Duron-D750AUT1B-750-Mhz-Socket-A-462-/170831458841?pt=CPUs&hash=item27c6593219
its about $10 with shipping.

My $2 estimate was based on prices in my country and, looking at ebay prices, was too optimistic, sorry.

EDIT:
Another thought - try to get new speaker first, to check if board is signalling any errors.
I assume you have tried clearing the CMOS?

Yea, first thing I did was clear CMOS. I wasn't able to get a speaker but I did get a CPU to test and, well, same problem. At this point I think it's safe to assume the mobo is just plain dead.