Calling the Geek oracle (hardware question) ...

Jerry Freeman · Post by **Jerry Freeman** » Thu Jan 19, 2006 7:27 pm

I'm still trying to squeeze a little more performance out of my IBM Aptiva 2174.

It came with an Anigma S30 motherboard and a 500 MHz Athlon K7 slot A CPU. I've purchased a K7 Thunderbird slot A (not socket A) 950 MHz CPU, but it doesn't work.

I've done a lot of reading, and everything I can find tells me the motherboard will take up to 1GHz and the K7 Thunderbird slot A CPU should just plug in and work fine.

The seller will send me another one in exchange to try if I suspect the CPU isn't working properly, but I wanted to ask around and see if anyone knows another reason it wouldn't work or if there's something I need to do to get it to work.

When I turn the computer on with the new CPU installed, I get thick white horizontal bars on the screen and it doesn't boot up. Then when I put the old CPU back in, everything's completely normal.

Thanks in advance for your help.

Best wishes,
Jerry Freeman

Daniel_Bingamon · Post by **Daniel_Bingamon** » Thu Jan 19, 2006 7:44 pm

Sounds like the video is unable to initialize because the main processor isn't running, I would suspect that those bars are just random patterns of memory being display. I remember from early days that some memory initializes with an all ones page and then an all zeros page, this would be deciphered by bit-mapped video as bars.

Memory code for black 0x00, 0x00, 0x00 and white 0xff, 0xff, 0xff that would make sense.

Feadin · Post by **Feadin** » Fri Jan 20, 2006 6:07 am

Jerry,

I believe it may be a power issue... the original Athlon 500 worked with 1.6V, but the TBird 950 uses 1.75V... maybe you have to switch your motherboard to this higher voltage. Do you have the user manual or any info about the jumpers and/or switches on the MB? Or you can also try looking for this on the BIOS...

You can see some info about processor specs here:
http://www.geek.com/procspec/amd/k7.htm
http://www.geek.com/procspec/amd/k7ultra.htm

Good luck!

Tyler · Post by **Tyler** » Fri Jan 20, 2006 7:01 am

Feadin wrote:Jerry,

I believe it may be a power issue... the original Athlon 500 worked with 1.6V, but the TBird 950 uses 1.75V... maybe you have to switch your motherboard to this higher voltage. Do you have the user manual or any info about the jumpers and/or switches on the MB? Or you can also try looking for this on the BIOS...

You can see some info about processor specs here:
http://www.geek.com/procspec/amd/k7.htm
http://www.geek.com/procspec/amd/k7ultra.htm

Good luck!

Y'know, I think you might be right on. Something similar happened to a friend and I recently while we were trying to put together a homebrew computer controlled fast-scan TV reciever; some of our processing equipent was not matched with proper voltage and the result was a really choppy picture.

Jerry Freeman · Post by **Jerry Freeman** » Fri Jan 20, 2006 7:35 am

Thanks for that.

My understanding is that the voltage setting and bus speed multiplier setting are on the CPU PCB, not the motherboard itself.

This is a board/CPU configuration that a lot of people have found suitable to overclocking, so it seems like the motherboard should accept various CPU speeds. I've seen discussions where the posters were certain this kind of board would take up to 1GHz.

Here's the relevant thread:
http://www.suggestafix.com/index.php?ac ... 22&t=15507

There's more info available about the K7 and K7 Thunderbird CPU by following the links in some of the comments in that thread. If you look at the overclocking articles, they reference the CPU circuit board, not the motherboard, for making changes in voltage and multiplier settings.

The seller has more of these CPU's in stock, so I'm thinking I'll exchange the one that isn't working and see if another one does the same thing.

Best wishes,
Jerry Freeman

fearfaoin · Post by **fearfaoin** » Fri Jan 20, 2006 10:04 am

Jerry Freeman wrote:My understanding is that the voltage setting and bus speed multiplier setting are on the CPU PCB, not the motherboard itself.

Well, it's on both. You can change the voltage and clock multiplier that
will be supplied to the chip at the CPU daughterboard, but you also
can change the Front Side Bus speed and voltage that the motherboard
supplies to the CPU daughterboard. This is what non-overclockers
have to do when changing chips. The articles you point to are useful
only if you already have the motherboard supplying the correct
Bus speed and voltage. AMD does not want you messing with the
CPU PCB, it voids the warrenty and should not be necessary for
normal use. You'll definately have to make a motherboard adjustment:
your bus speed should be the same, but the voltage needs to be 1.75

Jerry Freeman · Post by **Jerry Freeman** » Fri Jan 20, 2006 10:50 am

I'm not sure this is true.

On another bulletin board, I found this:

I have a 950 amd athlon in my ibm aptiva 2174 590. I just put it in and it worked. I had a 550 athlon.

This is the same motherboard I have and the same change of CPU speeds and voltages (1.6V - 1.8V).

I think I need to go ahead and exchange the upgrade CPU and just try it out to see what happens.

Best wishes,
Jerry

fearfaoin · Post by **fearfaoin** » Fri Jan 20, 2006 12:35 pm

Jerry Freeman wrote:
I have a 950 amd athlon in my ibm aptiva 2174 590. I just put it in and it worked. I had a 550 athlon.
This is the same motherboard I have and the same change of CPU speeds and voltages (1.6V - 1.8V)

Hm. Maybe it does autodetect... Interesting.
Good luck w/ the exchange.

Feadin · Post by **Feadin** » Fri Jan 20, 2006 12:42 pm

If the motherboard were really suitable for overclocking then you'd be able to change the volage setting directly from the bios

But I agree you should try a new processor if you can. That would really simplify things.

And about the last post, a 550Mhz 1.6V procesor may work just fine at 1.75V, so the motherboard MAY have been at 1.75V from the beggining...... I know it's a bit weird but it can happen

fearfaoin · Post by **fearfaoin** » Fri Jan 20, 2006 12:46 pm

Feadin wrote:If the motherboard were really suitable for
overclocking...

IBM says they don't support any upgrade of processor,
so I don't think overclocking was a critical part of the design...

Tyler · Post by **Tyler** » Fri Jan 20, 2006 12:50 pm

fearfaoin wrote:
Feadin wrote:If the motherboard were really suitable for
overclocking...
IBM says they don't support any upgrade of processor,
so I don't think overclocking was a critical part of the design...

Yeah, but they only say that so you'll go out and buy their new model with go-faster stripes

fearfaoin · Post by **fearfaoin** » Fri Jan 20, 2006 2:42 pm

Tyler Morris wrote:Yeah, but they only say that so you'll go out and buy their new model with go-faster stripes

Word. I painted flames on the side of my box, but it didn't go any
faster. I did run 10degrees hotter, though. </bs>