Overclocking an i3 540

ShakeNBake · 21 Oct 2010 at 00:57

Potential System Setup:

i3 540:
Stock speed = 3.06 GHz
Multiplier (locked) = 23x
3060 / 23 = 133 MHz Base Clock

Motherboard:
Gigabyte GA-H55M-UD2H Intel H55 (Socket 1156) DDR3 microATX Motherboard [GA-H55M-UD2H]
(used in some of the overclockers.co.uk OC i3 full system builds)

RAM:
OCZ Gold 4GB (2x2GB) DDR3 PC3-10666C9 1333MHz

Total cost in this week's sale = ~£200 (+ a GTX 460 1024MB)

So overclocking settings on this setup.

I am looking for a light overclock for gaming, possibly on stock cooler (but maybe will consider buying an Arctic Cooling Freezer 7 CPU cooler). I do not want to turn up volts too much.

So if I got this right:

the RAM will be at 1333 MHz, which you divide by 2 to get to 667 MHz.
what kind of ratio does this have to be in with the CPU's Base Clock?

at stock settings, it would be 133 : 667 which = 1 : 5

so if I was to increase the Base Clock to 167 MHz, it would be 167 : 667 which = 1 : 4

base clock of 167 x 23 multiplier = 3841MHz...?

if I wanted to hit 4GHz, I would need a base clock of 174 MHz...?
4.2GHz = 182MHz base clock...?

Question 1: Does the base clock : memory ratio need to be a certain value to get a stable overclock? i.e. does running a base clock of 174 or 182 MHz and a memory speed of 667 MHz (->1333MHz) give a stable overclock

Question 2: Is it worth it to buy an aftermarket cooler for £20 or so?

Question 3: Does the i3 540 CPU come with thermal compound pre-applied to the intel heatsink, or do I need to purchase some?

(I have some experience overclocking a Q6600, but things have changed a bit from LGA 775 -> LGA 1156...)

cmndr_andi · 21 Oct 2010 at 01:16

Hi there

1) The ratio is less important than the actual RAM speed. Try to keep it at or below 1333MHz (667MHz actual) - so lower the memory multiplier if required. You don't want to overclock the RAM, just the CPU. Also, make sure the RAM is running at the rated voltage and timings.

2) Absolutely. The stock cooler is fine for stock speed - but when you do proper overclocking it won't be able to keep things cool enough.

3) There is thermal paste with the heatsink - bot great but it will do the job. If you go for the ACF7 - it comes with MX2 (good paste) pre-applied.

1Day · 21 Oct 2010 at 09:44

You can do amazing things with that combination. It really is the best value out there right now.

Not to put your hopes up into the realm of the unrealistic, but I was running my i3-530 (the smaller brother) at 4GHz on the stock cooler for the first two weeks while I waited for the cooler I ordered to come back in stock. Temps were not an issue the whole time. The point here is that you can clock your CPU to quite a respectable overclock as long as you let temps be your guide.

Do small steps and write down what your idle temps are and then run some CPU load application and write down what your temps are under load.

Have fun and enjoy.

ShakeNBake · 21 Oct 2010 at 13:40

bargain of the century?
gtx 460 price drop http://forums.overclockers.co.uk/showthread.php?t=18199013

(alrdy got see-through case with 4 fans, 700W PSU, 1TB HD, Windows 7 64-bit and all other stuff needed for gaming)

ShakeNBake · 21 Oct 2010 at 19:50

and now it's only £151.99 for the GTX460!!!
time to put in a purchase

cmndr_andi · 21 Oct 2010 at 20:02

Please bear in mind that the brand new AMD HD 6850 and 6870 are coming out tommorrow. If I were in your shoes I would pass up the £152 GTX 460, and see how the new cards compare in terms of performance and price. If the 6850 is very good, the normal price for a GTX 460 will likely go down.

ShakeNBake · 22 Oct 2010 at 00:23

I've always used nVidia so I'm not really interested in the ATI cards.
I've been watching the prices of the GTX 460's for a long time now, they have been dropped by overclockers.co.uk to £150 which is a price I am very happy to pay considering they were ~£200 on release.

I doubt the 460's will drop in price much more than they already have (after all these ZOMG NVIDIA PRICE DROP $$$$ forum threads).

I need to buy this week anyway, to get the savings on the cpu & motherboard. (~£30)

So ordered tonight ^_^

edit:
I looked up some more stuff about the RAM ratio's on LGA1156 sockets.
At stock, the RAM is running at 10x the base clock. You can also run at 8x or 6x.

I think a very stable overclock will be running at 8x ratio, memory @ 1333MHz, base clock @ 167 MHz, for ~3800MHz per core.
Otherwise, run at an 8x ratio with base clock at 174MHz, memory @ 1044MHz (hm), for 4000MHz per core.
Apparently I may need to up the voltage to 1.3v or 1.35v on vCore to get past 170MHz base clock.

Will probably end up running at 167MHz base clock with 8x ratio (especially for first few days/weeks as the thermal compound is settling), if I get lag in games with cpu maxxed out I will consider pushing it harder with a x6 ratio but higher vCore & base clock.

I will let you know how the setup goes, maybe post some pics

(Gotta build 2 PC's in one day, using my old parts to upgrade parents pc...! Should all be arriving on Monday fingers crossed).

edit 2: damn, looks like i should have got some 1600MHz RAM for 8x multiplier, 200MHz base clock. Might have to order some at a later date, and sell on the 1333MHz sticks.
Will end up just running @ RAM 8x (1333MHz) Base Clock: 166.67MHz for ~3.8GHz, shame cos these cpus can hit up to 4.6GHz with the 1600MHz RAM.

edit 3: looks like it's my lucky day :3
ordered - http://www.overclockers.co.uk/showproduct.php?prodid=MY-041-PA
for £65 including postage on super sale, can send back the un-opened 1333MHz RAM for a £65 refund.

yay!