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General discussion

Adding ram w/different clock speeds

Feb 4, 2004 7:04AM PST

I just bought a 512 Mb stick of ram to add in my computer.It's PC 2700 at 333MHz
I have a pentium 4cpu 2.4GHz with a 533MHz bus and this is in the specifications section in my book.
"DDR 333 only on computers with 533-MHz system clock speed"
"DDR 266 on computers with either 400- or533-MHz system clock speed"
The module that I pulled out was a 256Mb PC2100 at 266MHz. Ok the 512Mb of ram works fine. My question is, can both 256Mb PC2100 at 266MHz and my new 512Mb PC2700 at 333MHz be added in both slots for768Mb of ram? Someone told me yes it will just end up running at the slower speed of 266MHz. Is this right?


Thanks in advance

Discussion is locked

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Re:Adding ram w/different clock speeds
Feb 4, 2004 9:34AM PST

"DDR 333 only on computers with 533-MHz system clock speed"
"DDR 266 on computers with either 400- or533-MHz system clock speed"
The module that I pulled out was a 256Mb PC2100 at 266MHz. Ok the 512Mb of ram works fine. My question is, can both 256Mb PC2100 at 266MHz and my new 512Mb PC2700 at 333MHz be added in both slots for768Mb of ram? Someone told me yes it will just end up running at the slower speed of 266MHz. Is this right? That is what is supose to happen but in reality your computer may not even boot or it will be unstable and may even corrupt your harddrive. Please go an buy the correct ram, a matching pair in speed.

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Re:Adding ram w/different clock speeds
Feb 4, 2004 11:25AM PST

The system will go as fast as the slowest ram provided it allows both installed. Remove the 2100 and use just the 2700. Verify under the bios(if optionable) to reset the ram settings to run at the newer 2700 level, osme systems that maybe an *automode* feature and does it does its own config.. If you're allowed both raM installed at the higher speed, it will probaly become unstable as the 2100 is pushed, so expect that. Shop around for more 2700 ram as pricing at the big boxes tend to offer sales now and then at decent prices.

good luck -----Willy

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Re:Re:Adding ram w/different clock speeds
Feb 4, 2004 8:09PM PST

Thanks for the replys. Dell tech support are the one that told me I could put both modules in. I figured that it might not be the best thing to do, I figured I'd get another opinion.

Kingston ram KVR333512R $89.99 with a $40.00 mail in rebate total price $49.99 Circuit city seems like a good deal to me.

Thanks again

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Re:Adding ram w/different clock speeds
Feb 4, 2004 9:46PM PST

Your processor will only run as fast a the PC2100 memory will support. If you use faster memory it will run at the lower speed. You can mix the memory since the processor cannot take advantage of the extra speed of the PC2700 you bought, it only run at PC2100 speed.

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Re:Adding ram w/different clock speeds
Feb 4, 2004 11:53PM PST

All I've heard it's not reccomended but wont hurt to try. Ram is cheap. If your PC becomes unstable, remove it. Always reccomended to match RAM