Thinkpads Forum

Very strange. I have 600X 2645-4EU that came stock w/ PIII 500.

I bought a MMC-2 PIII 850 through eBay and installed it. It would boot fine through BIOS, but as soon as Windows took over, it would freeze. I would have to unplug AC adaptor (with batter in) and it would progress booting for a few seconds, then freeze. I would have to plug AC adaptor back in. That's the only way it would run, toggling AC back and forth. I contacted seller and told him that CPU was bad, assuming speedstep was going nuts. He sent me another 850. I put it in and it ran stable. It booted flawlessly into XP at 847mhz w/AC adaptor, 697mhz on battery alone. I found that if I booted w/AC, I could unplug AC and it stayed at 847mhz on the battery. I could live with that. It woked fine for 2 weeks, until I changed to another AC adaptor.

Here's the issue:

The AC adaptor I was using was a generic 19v 3.16a that I used interchangably with my ThinkPad and my HP laptop. It's the only one I had for both laptops, so I decided to get another one. I got an IBM one specifically for the ThinkPad, 16v 3.36a.

The second I plugged it in, the exact same freezing I had with prevoious CPU started. I switched back to generic AC adaptor, but problem persists. I tried dumping the HD, re-partitioning and re-formatting but problem persists.

Does anybody know what the heck is going on? Is this a SpeedStep issue, and, if so, is there a way to mod this CPU to lock it at 850?

ANY help is GREATLY appreciated!

Thanks in advance

I use to rebuild and upgrade 600 series machines, but I admit it's been awhile...

The 1st thing that caught my eye is the 2645-4EU isn't a speedstep machine. If my memory serves me correctly the 5f and 9f machines are the only SS 600x's.

A non SS machine will/should run 150 MHZ slower, so your machine would only run at 700 mhz max....

Again just going from memory there's a lot of confusion on running SS CPU's on non SS 600x's... Sometimes they work, sometimes they don't... Sometimes you may get 850 mhz, other times you may get it but when the machine tries to change speeds it will cause lock-ups.

If it locks-up on boot try pushing fn+f2 and see if that helps..

My 600x 2645-4EG (non-SpeedStep) runs fine...

700MHz on battery
850MHz on power line with battery installed
700MHz on power line without any battery

...and without any mod on processorboard or mainboard.

I've only changed the processor-driver in system setup... there are 3 drivers, normally xp use the first one 'Intel Pentium (III?)Processor' - I took the last one 'Intel Processor' manually, with driver called 'processr.sys'

Sometimes, very rare, the processorspeed is only 233MHz - when system came up from sleep-mode. After reboot it will work fine.

u.mac wrote:My 600x 2645-4EG (non-SpeedStep) runs fine...

700MHz on battery
850MHz on power line with battery installed
700MHz on power line without any battery

...and without any mod on processorboard or mainboard.

I've only changed the processor-driver in system setup... there are 3 drivers, normally xp use the first one 'Intel Pentium Processor' - I took the last one 'Intel Processor' manually, with driver called 'processr.sys'

Sometimes, very rare, the processorspeed ist only 233MHz - when system came up from sleep-mode. After reboot it will work fine.

Yeah, thats where the confusion comes from...If you read through all the 600x threads here there seems to be no set reason to how these 600x machines will handle SS CPU's...Officially the 5Fx and 9Fx machines should be the only machines that should handle SS cpu's. But that doesn't always seem to be the case...

Before changing processordriver, system runs only 700MHz - under all circumstances.

May be ACPI tells processor and driver how to work.

I don't know, how my 600x will work with Win98 and APM.

I've had this issue with a 650MHz CPU in a non-SS board. When the machine hangs, press Fn-F2 for a quick way to get going, but it will hang a lot.

To fix it, boot into safe mode, and change the CPU driver to... something different . I can't remember the setting right now, but it's the generic, no-frills CPU, and the machine will never lock up again.

OK, thanks everybody. My keyboard is defunct. I guess I damaged the ribbon cable when re-assembling. I'm bidding on another keyboard on eBay. When I get it, I'll re-assemble, reload XP Pro and try changing the driver. I'll post back then.

I also have a 600X 2645-4EU that came stock w/ PIII 500 now sporting a 850mhz cpu, it works perfectly i only had to swap cpu's turn on the pc and change the driver from "PIII" to "intel processor".

No issues so far.

cmarti wrote:I also have a 600X 2645-4EU that came stock w/ PIII 500 now sporting a 850mhz cpu, it works perfectly i only had to swap cpu's turn on the pc and change the driver from "PIII" to "intel processor".

No issues so far.

I thinking about upgrading my 600X; and would more details about changing the driver from "PIII int "intel processor". Are you doing this in the Device Manager? Are you running XP Pro?

Thanks!

HarryWild wrote:
I thinking about upgrading my 600X; and would more details about changing the driver from "PIII int "intel processor". Are you doing this in the Device Manager? Are you running XP Pro?

Thanks!

Yes i have XP Pro and to change the driver you need to go to control panel then system and device manager there right click on the processor and select update driver, search driver manually and select the second driver from the list.