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chromonium

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Processor upgrade??

I have an 2 year old pc from time, witha CyrixInstead processor, i have some new spairs as well, from another computer including a new Pentium 3 processor.

Can I replace the Cyrix with teh pentium or not??

adam
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jhance

In theory you can with most motherboards but I've not had good success in upgrading Cyrix CPUs.  Most recently I had a Cyrix "300" and tried to put an AMD K6/450 in it.  The motherboard was supposed to be compatible and the jumpers supported it but I never could get reliable operation.  My theory is that the MB was "tweaked" by the manufacturer for the Cyrix idiosyncracies and that made it less compatible with other chips.

The upgrade is not all that useful, however, since the best possible speed you can get in a Socket 7 CPU is an AMD K6/500.  With 1.7GHz and faster CPUs on the market today, it just doesn't make sense to do this.

Spend a bit more and get a new MB and a 1GHz or so AMD Athlon.
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ive got the other processor, anyway, do you think I should try it??
If you already have another processor you have little to lose by trying it out.
but can it blow the MB and computer by doing so??
Yes, it could but I'm assuming that:

1) Your motherboard is compatible with the new chip you have.  (Most likely it is since Socket 7 designs are pretty generic)

2) You have some user manual or other information to guide you.

3) You have some idea about what you are doing.

If all of the above are true, please proceed.  Otherwise, get an experienced friend to help or take it to a reputable shop.
There is very little risk to the MB but you do need the jumber settings.  If you don't have the book that came with it, they may be printed on the MB itself, or, your going to have to get them off the web.

All this assums that your MB will support the newer CPU.

hw
yeah, but i dont know whether it will support it, that is what im asking you!!!


NO, you won't be able to fit a Pentium III in the socket a VIA/Cyrix 686/MII  CPU came out of. I have to assume you are not talking of the new P2 class Via/Cyrix chip for socket 370, because they weren't around 2 years ago. The chip you are talking about must be in a socket 7 motherboard, which won't take an intel CPU better than 233MMX.

If you have the PIII motherboard, sure, go ahead, replace the guts of the Cyrix system with that. Cross your fingers the PSU is up to it, 250W should be fine, but if it's an "economy" sized 160W or 200W, you might need another case/psu.

Machines that were built new by OEMs with Cyrix CPUs were usually the cheapest, most cut down, penny scrimped machines on the market, therefore they have just about the minimum requirements to run the CPU they were supplied with. Now, the reason JHance may have had troubles with a K6-2 on machines such as this, is more likely to be an issue with the amount of power the onboard regulator can provide to the CPU, because the faster K-2s require more amps than Cyrix CPUs and therefore many boards while having some K6 support are not capable of supporting the faster CPUs reliably due to overburdened voltage regulators. However, some manufacturers may have offered the Cyrix CPU on the same platform they were offering more expensive and faster AMD CPUs, as a lower cost option on their standard range, so depending on the build quality of the system, it is possible that a fast K6 will work nicely in it.

Also, machines from big name manufacturers like Compaq et al, usually only support the CPU they were supplied with, even if they have an OEM version of a standard motherboard in the system, they often have a special BIOS, and this is usually the problem when it comes to upgrading. Gateway for instance is infamous for supporting Intel CPUs only in it's systems. Also, Cyrix CPUs were available in high PR ratings for a low actual clockspeed, PR300 say with 233Mhz internal, but were voltage compatible with older 233Mhz motherboards designed just for intels MMX chips,  therefore some manufacturers cleared out their older boards by selling them with PR300 Cyrix chips on, making them look like a good deal alongside their PII-300 systems, the faster K6-2s and K6 Littlefoot (266, 300) CPUs needed 2.4 and 2.2 core voltages that were not available on these older boards. That's just extra info really, to explain observations about Cyrix CPUs being difficult to upgrade.

As I recall, Time is not really a premier league OEM, so is more likely to have a standard motherboard, so if you find out the model and manufacturer of that, there may be a manual and BIOS updates available for download that would ease installation of a faster CPU from AMD. However, I think you will find that for games etc, an Intel 233MMX if you can get one could also be considered an "upgrade" to a Cyrix Chip. My MII PR366, which is actually overclocked and by Cyrixes scaling should qualify as the PR400 model, only benchmarks as fast in most modern benchmarks as a P200 or P233. (older benchmarks are based on older usage requirements, including legacy dependance on 16 bit code, in THOSE, it still scores as fast as an intel 400 or so) So for modern 3D games etc, you need about twice as much "PR" on a Cyrix  for the same performance as intel. However, for all it's abysmal FPU and gaming performance a cyrix still will seem to live up to it's "PR" when used for browsing and wordprocessing etc in windows, so if replacing one with a "slower" intel CPU, you may initially feel dissappoi9nted as your GUI performance takes a small hit, but you will soon begin to appreciate the upgrade when you begin to really work the CPU.

regards,

Road Warrior
what speed does the Cyrix MMX II run at then??
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RoadWarrior

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yeah, youre right, thankyou

it is about 224.9 - 225 Mhz
what is 3DNow ???, coz its not supported by my processor
chromonium, I have added points to your account to be more fair for the Experts.  I will bring the question points up to 50 for each to the two questions you have open.

Thanks,
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jhance, I want to aploigize to you for asking you to tone down yersterday, your comment was approprite.  The Locked question had made me angry.

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Hi all,

This question has been open for quite awhile. I am going to allow feedback from the questioner and experts. If it is not resolved, I will delete or accept an answer based on the info I have been given. Experts, feel free to offer input, or even suggest who you  think is correct. I will monitor this question for a period of 5-7 days and come back and evaluate this question.

Questioner, if you were helped, chooses whom you would like to award the question to, and Accept Comment.  It is your responsibility to complete this question.

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