Celeron SL54P... upgrade options?

[VulcanTourist]

I have a Toshiba Satellite 1805-S203 laptop, which has a Celeron SL54P 800MHz CPU in it, which is an FC-PGA package and sits in a Socket 370. Might it be possible to upgrade that with another mobile CPU from the same era, one that has the socket, package type, FSB and core voltage requirement, say for instance the Pentium III SL5QV? Toshiba had a model 1805-S253 in the same series which did in fact sport an 850MHz Pentium III chip.

[Mixeur]

Celeron SL54P 800MHz is not a mobile CPU at all, but a desktop one.
It is not sure at 100% that SL5QV would work in it, but I think you have great chances.

[Wizzard1]

Your laptop may support a PIII 850/100, and may even support up to the PIII 1100/100 or Celeron 1100/100 Coppermine processors. Tualatin support is VERY iffy, and remember: With a processor upgrade (like this) come increased thermal output- Make sure your cooler is sufficient.

[Guest]

Wizzard1:

Thanks for the optimistic conclusion. Can you reference a specific model number or three, so that I know what to scavenge? I am quite bewildered by the innumerable variations and not sure I'd find the "right" CPUs!

Alternatively, what specific characteristics should I be comparing to ensure compatibility? I am especially unsure of the multiplier: I can't recall if that is dependent upon the BIOS at all, or whether it is dictated entirely by the processor? Am I perhaps recalling struggles between "locked" and "unlocked" CPUs? I'm guessing my choices in this case would all be locked? Other than that, I thought that socket type, package type, front side bus speed, and core voltage were all I needed to compare; are there other factors?

(The reason I'm motivated to do this is because I received this laptop gratis recently, but have found that the stock system can't play ANY video content at all! It can barely manage to play an MP3 file, causing choppiness at the start and pegging the CPU at 50-75% while playing it. That is pretty unacceptable. While I don't think it should be happening with a Celeron 800, I can't identify any other cause other than the CPU being underpowered.)

[VulcanTourist]

I can clearly see that Tualatins aren't going to work; although I found the necessary FC-PGA2 socket adapter for sale, it adds 3/8" to the height of the CPU stack, which in a cramped laptop is a dealbreaker!

So it seems I'll have to stick with Coppermine Celerons and Pentium IIIs. I'm going to shoot for the SL5QW moon, I think, with a SL5QV as a second choice. The SL5QW generates about 40W as opposed to the SL54P's 30W, but I don't know how that translates into operant temp differences. Apparently the PIII-850 used in that other Satellite model dissipates the same wattage as the Celeron in this one; that might be a fallback, since a PIII should still perform a bit better. I'm convinced now that some degree of upgrade is definitely possible, it's just a question of how much. I'm not worried about heat dissipation; I'll mod the heatsink and fan assemblies as needed to accommodate the increase.

If you guys have any more specific insights, please do share before I get impatient and buy something I'll regret!

[Wizzard1]

Just get some more airflow, and use proper thermal interface You'll be OK.

[Neon_WA]

For the 1805 series PS183U model the top four processors are

RB80526PY005.Intel PIII 1.10GHz
RB80526PY001.Intel PIII 1.0GHz
RB80526RY005.Intel Celeron 1.10GHz
RB80526RY001.Intel Celeron 1.0GHz

so if the model you have is newer than the PS183, then you should be right

[VulcanTourist]

The 1805-S203 is a PS181U- part number. I suspect the PS183U- systems used a 495-pin socket, not FC-PGA Socket 370 like this one. If so, none of the CPUs from those models would even fit in this one!

[Neon_WA]

[VulcanTourist]

Well, wait a minute, now: the SL5QV is exactly the same as the SL5QW except that the clock multiplier is 10 instead of 11. All the other parameters are the same, yes? If so, how could the clock multiplier alone be a dealbreaker? Why do you say it's a definite no-go?

BTW, how did you go about tying those CPUs to the PS183U and PS181U, anyway? How did you investigate that?

[Neon_WA]

[VulcanTourist]

I actually had found what looked like a much cheaper auction for an SL5QW and placed a bid, but the bidding skyrocketed up to $38!

My fallback was a buy-it-now offer of a SL5QV, which I have bought for less than $10 total (I'm actually trying to haggle the shipping but it's doubtful).

There were equivalent Celerons, but I judged that they wouldn't be enough improvement to be worth the effort. Someone also offered me a SL5XS for free, but we had already established that Tualatins aren't compatible (and the adapters aren't an option).

I have my fingers crossed that it will (a) work and (b) solve the poor performance I was observing. Lord knows if the cause is the video subsystem I'm up that proverbial creek.

Since I received so much feedback here, I will try to remember to report the results. Some other lover of antiquities may try the same thing and find this thread helpful.