Faster RAM = better CPU overclock?

[booseek]

Does faster RAM affect my CPU overclocking capabilities? I recently purchased a pair of Corsair XMS 4GB DDR3 @ 1333MHz / 9-9-9-24 / 1.5V sticks for around $68 off of TigerDirect (discount, rebate, Bing Cashback - sold out the first day) and I'm wondering if I made the right decision if I plan on overclocking my CPU. I don't really care about overclocking the RAM, but I do plan on getting an i5 to at least 3.6GHz or the 1055T/1090T to at least 3.8. Should I have any problems doing this with a good motherboard? Or should I have went for a 1600 / 7-8-7-24-2N / 1.65V set for $120?

 

[enzo matrix]

when you change the base clock, it increases the ram speed also. But if you want to keep the ramspeed as is, just reduce the ram multiplier as you increase the base clock.

 

[booseek]

Thanks for the quickly reply.

I understand that increasing the CPU clock increases the ram clock and that it is possible to then decrease the RAM clock to its near default value. Is that all there is to it? Does such a drastic difference between both frequency values (overclocked CPU, default RAM) affect stability?

 

[JackNaylorPE]

Here's a quick table using an i7-930 as an example

133 BCLK x 21 CPU Multiplier = 2.8 GHz
133 BCLK x 8 Memory Multiplier = 1066 MHz

167 BCLK x 21 CPU Multiplier = 3.5 GHz
167 BCLK x 8 Memory Multiplier = 1333 MHz

200 BCLK x 21 CPU Multiplier = 4.2 GHz
200 BCLK x 8 Memory Multiplier = 1600 MHz

BIOS values, that I have seen anyway for Memory Multiplier range from 6 to 14 (even numbers only)

 

[booseek]

Here's a quick table using an i7-930 as an example

133 BCLK x 21 CPU Multiplier = 2.8 GHz
133 BCLK x 8 Memory Multiplier = 1066 MHz

167 BCLK x 21 CPU Multiplier = 3.5 GHz
167 BCLK x 8 Memory Multiplier = 1333 MHz

200 BCLK x 21 CPU Multiplier = 4.2 GHz
200 BCLK x 8 Memory Multiplier = 1600 MHz

BIOS values, that I have seen anyway for Memory Multiplier range from 6 to 14 (even numbers only)

Thanks for the info.

Would I be able to up the CPU multiplier (given that the multiplier is unlocked) to 4.2 GHz and down the memory multiplier back to default with 1333 MHz RAM?

 

[japps2]

boo,

unless you have an extreme CPU chip, you won't be able to change the multiplier. Read the overclocking guilds and have a good aftermarket heatsink to keep the CPU cool. And download programs to test for heat and to run stress tests to see if you can take the overclock. I like intelstresstest for testing and cool temp for monitoring...both free.

Better ram helps, but only minorly...the difference between DDR3-1067 and DDR3-1600 was only like 5% in real world apps.

 

[paigeinfull]

plus the ram will likely overclock easily to 1600 since its rated at 1.5 volts

 

[loneninja]

Thanks for the info.

Would I be able to up the CPU multiplier (given that the multiplier is unlocked) to 4.2 GHz and down the memory multiplier back to default with 1333 MHz RAM?

If you have an unlocked multiplier on the cpu, and you overclock by only increasing the cpu multiplier, than your memory isn't overclocked.

 

[jimmysmitty]

If you buy faster RAM then it will be easier to OC without having to mess with the RAM.

So if you get DDR3 1600MHz RAM then you can OC the CPU to a 1600MHz RAM clock without worrying about it having stability issues.

Thats why I got my 1066MHz DDR2 when everyone else went for DDR2 800. Makes OCing the CPU easier.

 

[hundredislandsboy]

Does faster RAM affect my CPU overclocking capabilities?
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Generally, no. Usually, it's a good idea to overclock your CPU or RAM separately, not both at the same time. That way, it's easier to isolate stability issues.

 

[tater86]

Would I be able to up the CPU multiplier (given that the multiplier is unlocked) to 4.2 GHz and down the memory multiplier back to default with 1333 MHz RAM?

If you went with BCLK at 210, and CPU multiplier at 20, setting your memory multiplier to 6 would put your memory at 1260 with the CPU at 4.2, which would be close.

A BCLK at 220, CPU multiplier at 19,and memory multiplier at 6 would give you 1320 on the memory and 4.18 on the CPU. I don't know if you'd be able to be stable at a BCLK of 220 though.

There's an article about the impact of memory speeds here.

When I built my system (i7 920, no experience with the i5), I went with the 1600 because I felt like the 1333 was kind of an awkward position as far as BCLK and timings.

Then again, you could just give a try at 200 BCLK, 21 CPU and 8 memory, it may work at 1600.

 

[booseek]

Best answer selected by booseek.

 

[muzza150]

Hi wonder if anyone could help ive overclocked my 4820k to 4.7ghz under stress test im getting 60c my ram corsair vengeance 1600mhz its at 1333mhz if i put it 1600mhz the overclock fails if i was to buy higher frequency ram would that allow my overclock go above 4.7 and my memory to run more stable just wonder if its worth buying better ram?