Intel Xeon L5639 Hexa(6) Core LGA1366 Price:US $79.80 Used Ebay Seller

[MN Scout]

Bought a x5670. Hopefully it'll work as a quick drop in replacement for my bad clocking 920 - poor stepping. I sure could use a few extra GHz right now.

 

[primetime]

Bought a x5670. Hopefully it'll work as a quick drop in replacement for my bad clocking 920 - poor stepping. I sure could use a few extra GHz right now.

long as you have a decent mb and cooler...you be hitting 4400mhz no problem...its just a question of proper bios settings imo getting 200blck @ (22x) stable...if you list your mb...someone can chime in whats worked for them if you have issues..if you own an asus mb i can set you up very easily...someone else would have to help with different vendor possibly

 

[MN Scout]

long as you have a decent mb and cooler...you be hitting 4400mhz no problem...its just a question of proper bios settings imo getting 200blck @ (22x) stable...if you list your mb...someone can chime in whats worked for them if you have issues..if you own an asus mb i can set you up very easily...someone else would have to help with different vendor possibly

My computer right now:
Asus P6T Deluxe V1
CORSAIR HX3X12G1333C9 12GB PC3-10666 (DDR3-1333) - 6 sticks x 2GB.
Thermalright Ultra-120 eXtreme

Current bios is version 1003, I've downloaded 2209 and plan on installing it here in the next 2 days. Crossing my fingers nothing bad happens.

Been forever since I've messed with the overclocking. I'd like to keep the hyperthreading turned on and Turbo working if possible. 4GHz would be nice. Anything will be a nice upgrade.

 

[primetime]

My computer right now:
Asus P6T Deluxe V1
CORSAIR HX3X12G1333C9 12GB PC3-10666 (DDR3-1333) - 6 sticks x 2GB.
Thermalright Ultra-120 eXtreme

Current bios is version 1003, I've downloaded 2209 and plan on installing it here in the next 2 days. Crossing my fingers nothing bad happens.

Been forever since I've messed with the overclocking. I'd like to keep the hyperthreading turned on and Turbo working if possible. 4GHz would be nice. Anything will be a nice upgrade.

lol...you have the same board i have...i can give you exact bios settings for 4400mhz...hell you even have the same cooler lol...if you had the same speed ram i think we be using the same settings...but since you don't it be a little different

 

[primetime]

Here are the bios settings that work extremely well for mine (with the latest bios 2209)....you have different ram so that changes things a bit.....you be aiming to set the blck so it matches up well for 1333mhz ram

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i guess you might actually use the 24x or auto (24x or turbo25x) since you be using a different blck to match up with your ram speed....the voltages should work fairly well for you at least and
i think at around 170blck at 24x(25turbo) puts the ram around 1333mhz and should get you around 4080mhz to 4250mhz turbo...so regardless you be over 4ghz all the time

 

[Zoson]

>1.35v qpi is bad for gulftowns.

 

[primetime]

>1.35v qpi is bad for gulftowns.

Been running that voltage for close to year now and totally stable and cool....keep in mind its actually shows up as around 1.336 in windows...if trying much higher than this then the heat is hard to manage...i believe a few others here are actually running a tad higher here...if im not mistaken i was running very close to that on my old 920 for 5 years and never had an issuelol

you are right...the lower the better if possible...i should probably put some time into trying to see how much i can lower it without loosing any stability..but imo its not a bad starting point to find the best overclock

 

[MN Scout]

Thanks primetime. I'll try 170.

Thanks Zoson. I'll only up that if needed.

I'd like to get 2 more years hopefully out of this computer. Edit: I'm looking forward to installing it Thursday morning! Then testing, testing, testing....

 

[mat9v]

Hi all

I will be joining this small group of Xeon "lovers"
I just got Gigabyte G1.Guerilla board along with L5640 cpu. I will put it under ThermalTake Contac 30 cooler and while I will be overclocking it, my long term goal is to do so without rising voltage even a bit. I may try to squeeze every last Mhz out of it just for testing sake but unless it gives me a very large speed boost for small voltage change it will not stay overvolted. The board worked with 230 bus on i7 920 so hopefully I will be able to play a lot
The best is that it cost me an equivalent of 180USD for the combo

 

[Zoson]

Been running that voltage for close to year now and totally stable and cool....keep in mind its actually shows up as around 1.336 in windows...if trying much higher than this then the heat is hard to manage...i believe a few others here are actually running a tad higher here...if im not mistaken i was running very close to that on my old 920 for 5 years and never had an issuelol

you are right...the lower the better if possible...i should probably put some time into trying to see how much i can lower it without loosing any stability..but imo its not a bad starting point to find the best overclock

Ah, it's because you have LLC on Auto and not Full that you're getting droop.

920 is BLOOMFIELD, not GULFTOWN. The difference is bloomfield is 45nm transistors, and gulftown is 32nm. Smaller transistors cannot handle the same amount of voltage or heat. You're playing a different game now with different equipment.

Another difference is gulftown responds really well to LLC, while bloomfield did not.

Bottom line, I've been playing the 32nm game for 4 years and I've seen HUNDREDS of chips die because people exceeded the 1.35v limit, and if you take the time to look for _gulftown_ overclocking guides, you'll notice they ALL say to never exceed 1.35v due to killing random channels of your IMC.

 

[primetime]

Ah, it's because you have LLC on Auto and not Full that you're getting droop.

920 is BLOOMFIELD, not GULFTOWN. The difference is bloomfield is 45nm transistors, and gulftown is 32nm. Smaller transistors cannot handle the same amount of voltage or heat. You're playing a different game now with different equipment.

Another difference is gulftown responds really well to LLC, while bloomfield did not.

Bottom line, I've been playing the 32nm game for 4 years and I've seen HUNDREDS of chips die because people exceeded the 1.35v limit, and if you take the time to look for _gulftown_ overclocking guides, you'll notice they ALL say to never exceed 1.35v due to killing random channels of your IMC.

well then I'm glad you brought that up....like i said its been less than a year for me...ok so are we going to label what i was using safe or not safe since LLC is on auto or are we going to say start no higher than 1.34....guess i should try and drop mine a couple notches and see if it passes burn test anyway....less voltage is cooler anyway

 

[Zoson]

The thing you should be concerned with with LLC set to Auto is if your _idle_ QPI voltage is still below 1.35v real.

And yes, I always advocate using the absolute lowest voltages possible!

 

[primetime]

The thing you should be concerned with with LLC set to Auto is if your _idle_ QPI voltage is still below 1.35v real.

And yes, I always advocate using the absolute lowest voltages possible!

ok im a little confused....are we saying the QPI/Dram 1.4 core voltage is too high as well?

 

[Zoson]

ok im a little confused....are we saying the QPI/Dram 1.4 core voltage is too high as well?

Core voltage seems to be fine up to 1.45v or so.
QPI/DRAM(which is really VTT voltage and ASUS are being annoying) you should limit to 1.35v or less _real_ voltage(what your sensors read in bios).

With LLC Auto your voltage droops when you load your CPU, so your highest voltages will be when your cpu is actually idling, not when it's computing.

Also, for the record, I myself have damaged two gulftown cpus with high volts. My first 970 and my first 980x both suffered premature deaths because I gave them too much juice. It really hurt, because at the time that was like $1500 in 'shit i voided my warranty' losses.

 

[primetime]

was able to drop the v core 1 tick down and still pass...but i couldn't go 2 as it would crash during test...so i updated the original post with the lower passing voltage of 1.34...if i do get any crashes ill know just to raise it back up another tick...cause crashes are not something im used to getting...another reason i have kept this board so long...the x58 is the most stable board i ever owned

Also, for the record, I myself have damaged two gulftown cpus with high volts. My first 970 and my first 980x both suffered premature deaths because I gave them too much juice. It really hurt, because at the time that was like $1500 in 'shit i voided my warranty' losses.

could you not get it replaced under warranty from Intel....fuck it i would have at least tried

 

[Zoson]

was able to drop the v core 1 tick down and still pass...but i couldn't go 2 as it would crash during test...so i updated the original post with the lower passing voltage of 1.34...if i do get any crashes ill know just to raise it back up another tick...cause crashes are not something im used to getting...another reason i have kept this board so long...the x58 is the most stable board i ever owned

OK, It seems my engineers english has caused confusion:
vCore(CPU core voltage) is safe up to 1.45v
QPI/DRAM is only safe up to 1.35v.

ASUS incorrectly labels CPU VTT as QPI/DRAM.

Under load, because you have LLC Auto, all your voltages will be lower than set in bios.
At idle, your voltages will be just below, or equal to the voltages set in bios.

If you change to Full LLC, your voltages will be stable at what you set in bios under both load and idle conditions. Gulftown likes this. Bloomfield does not.
I.E. You will get higher overclocks with Full LLC on a Gulftown at lower amounts of voltage.

 

[PolRoger90]

My 980X doesn't seem to run memory at 2000MHz(+) speed without VTT being set to a minimum of ~1.335v (BIOS) /1.363v load (DMM). The previous owner ran this chip at a lower a memory speed with QPI/DRAM set to "auto".

I've noticed that BIOS programming seems to be rather heavy handed with VTT voltage settings for "Auto" rules.

 

[Haserath]

I'd be afraid of killing my chip using those voltages. I have found a stable spot at 200x20 with decent voltages. Memory is at 1603.

My qpi voltage is 1.225. I haven't tested lower yet. I'd be surprised if you need 1.3V for any Westmere at 200bclk. This is the Uncore voltage, which is everything except the 'core' and IMC. Idk why they even labelled it DRAM, except the L3 runs at twice the clock.

From what I understand, CPU PLL is not able to help stability whatsoever. It's a supply voltage to the cpu that gets 'clipped' down to say . 8V or other voltages. That's also probably why many people find lowering it helps stability as it may interfere instead of help. Wish I could lower it. :/

CPU differential amp may or may not help. Pulse height(strength) is really only if your cpu needs it. 800mv is 30% higher than the stock 610mv, and that's all going into heat.

I don't like using Load Line Calibration myself. I have it off. If you have it set at say, 1.35V, when you load and unload the processor there are still voltage dips/spikes so you'll have the range of 1.28-1.42V but only for a small time, which is what Intel's specification accounts for(and LLC goes against).

 

[PolRoger90]

I would be surprised to see any Westmere overclocked running 12 threads load at DDR3-2000(+) with much less than ~1.3v VTT (qpi/dram).

 

[Zoson]

Some corrections to your understanding:

My qpi voltage is 1.225. I haven't tested lower yet. I'd be surprised if you need 1.3V for any Westmere at 200bclk. This is the Uncore voltage, which is everything except the 'core' and IMC. Idk why they even labelled it DRAM, except the L3 runs at twice the clock.

CPU VTT/Uncore(or as asus calls it, QPI/DRAM) voltage powers the IMC. This is precisely why people see their IMC's dying/losing memory channels/degrading when they raise this value too high.

CPU differential amp may or may not help. Pulse height(strength) is really only if your cpu needs it. 800mv is 30% higher than the stock 610mv, and that's all going into heat.

I've also never found increasing the differential amplitude to be useful. Even at extreme speeds it didn't seem to do anything.
I found PWM frequency to be more useful, it allowed me to reach 5.6GHz at 750kHz, and I run 500kHz for my everyday overclock. 1000kHz was not useful to my watercooling - but may be with LN2.

I don't like using Load Line Calibration myself. I have it off. If you have it set at say, 1.35V, when you load and unload the processor there are still voltage dips/spikes so you'll have the range of 1.28-1.42V but only for a small time, which is what Intel's specification accounts for(and LLC goes against).

Right, it IS intel's spec to allow for voltage droop. What the spec is, and what actually works, however, are two completely different things. I would consider a 4GHz overclock 'on the top end of mild' and wouldn't require LLC. When you're shooting for 4.5+ it becomes noticeably helpful.

 

[Haserath]

I would be surprised to see any Westmere overclocked running 12 threads load at DDR3-2000(+) with much less than ~1.3v VTT (qpi/dram).

Oh, I was specifically talking about Primetime's overclock. I forgot about faster mem speed.

Yes, DDR speed higher than 1600 will need more VTT because the L3 will need to be faster. 12MB of L3@4Ghz would be quite the feat.

 

[Haserath]

Some corrections to your understanding:

CPU VTT/Uncore(or as asus calls it, QPI/DRAM) voltage powers the IMC. This is precisely why people see their IMC's dying/losing memory channels/degrading when they raise this value too high.


I've also never found increasing the differential amplitude to be useful. Even at extreme speeds it didn't seem to do anything.
I found PWM frequency to be more useful, it allowed me to reach 5.6GHz at 750kHz, and I run 500kHz for my everyday overclock. 1000kHz was not useful to my watercooling - but may be with LN2.

I keep flip flopping back and forth on it. It makes sense that it would be all of the uncore and the Dram voltage is for the DIMMs only(but still has an effect on Intel's controller?).

I always assume the CPU is limited by switching speed instead of switching strength so I'd agree with keeping the amplitude low. I have only overclocked a total of two CPUs now and not with any extreme clocks, so it was a 'maybe' for me.

I guess the asus bios doesn't have PWM. It looks like a higher frequency would actually control voltage better. This looks like it'd be a useful setting with LLC.

 

[Zoson]

I keep flip flopping back and forth on it. It makes sense that it would be all of the uncore and the Dram voltage is for the DIMMs only(but still has an effect on Intel's controller?).

DRAM voltage affects the IMC and can ruin it because it affects the input voltage supplied by the DRAM bus to the IMC.

There's some talk out there saying that IMC degradation by high DRAM voltage is caused by exceeding Uncore/QPI by 0.4v. So if you run your Uncore/QPI at 1.35v, you can run up to 1.75v DRAM without damaging your IMC... But I've never tried it, and it seems like crazytalk to me.

I guess the asus bios doesn't have PWM. It looks like a higher frequency would actually control voltage better. This looks like it'd be a useful setting with LLC.

Ah, I assumed you would have the same options as my Rampage 3 Extreme, another ASUS board. I also have the ability to lower my PLL below 1.8v, all the way down to 1.2v even, but 1.35v works best for me for some reason...

 

[PolRoger90]

Ah, I assumed you would have the same options as my Rampage 3 Extreme, another ASUS board. I also have the ability to lower my PLL below 1.8v, all the way down to 1.2v even, but 1.35v works best for me for some reason...

What are the benefits of running lower PLL? Lower temps, improved stability? I haven't tried lowering my PLL yet... Still running default 1.8v.

I know every chip is different... But would you mind sharing your daily overclock voltage settings?... Vcore, VTT, PLL, IOH, bclk and multi? Kind of curious... It looks like you have a strong 990X.

 

[primetime]

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i ran several test so far today.....cpu voltage and qpi both have to be were there at or it fails intel burn test....exactly the same levels i had to use with my previous chip (5639) i can experiment more latter today with lower pll....but i already failed it once at default setting...so this is were im still at...it passes every time with these settings (so far)...this could be were the rampage and the p6tdelux are just different

 

[primetime]

My computer right now:
Asus P6T Deluxe V1
CORSAIR HX3X12G1333C9 12GB PC3-10666 (DDR3-1333) - 6 sticks x 2GB.
Thermalright Ultra-120 eXtreme

Current bios is version 1003, I've downloaded 2209 and plan on installing it here in the next 2 days. Crossing my fingers nothing bad happens.

Been forever since I've messed with the overclocking. I'd like to keep the hyperthreading turned on and Turbo working if possible. 4GHz would be nice. Anything will be a nice upgrade.

I totally forgot you could just adjust the dram freq to work with the slower ram and use the same overclock settings (actually at these settings the ram be slightly under clocked for what its worth)

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course its been mentioned the voltages are not safe...maybe there not idk....but its the same ones i been using since my 5639 chip...but i only had it for less than a year

if your board behaves like mine this will give you 4400mhz stable imo...and just so you know we can select 24x but it throttles down to 22x anyway at full load across all threads...you could get the turbo by selecting auto but its just for one or two threads anyway and i don't honestly believe our chips are stable above 4400mhz anyway.....even at these high voltages....i had no luck at even 4500mhz so i figure fuck it

 

[Brackle]

I totally forgot you could just adjust the dram freq to work with the slower ram and use the same overclock settings (actually at these settings the ram be slightly under clocked for what its worth)

course its been mentioned the voltages are not safe...maybe there not idk....but its the same ones i been using since my 5639 chip...but i only had it for less than a year

if your board behaves like mine this will give you 4400mhz stable imo...and just so you know we can select 24x but it throttles down to 22x anyway at full load across all threads...you could get the turbo by selecting auto but its just for one or two threads anyway and i don't honestly believe our chips are stable above 4400mhz anyway.....even at these high voltages....i had no luck at even 4500mhz so i figure fuck it

So Messing around with my chip today. I decided to put everything on Auto, except QPI voltage I was able to lower to 1.33v.

I have CPU PLL at 1.95 and. Now I am only stable at 1.43v @ 4.4ghz. That is with HT off...because I need 1.46v to be stable with. A little high for my taste (hell 1.43v is high for my taste, but I can deal with it).

Figure I will take Zosons advice on the QPI voltage and keep it lower then 1.35v.

 

[mat9v]

First overclocking tests for me. As stated I went for low voltage and power consumption, for 3.8Ghz I am using 1.175V and temps are really low (less than 50C after 30 minutes of prime95). Turbo is disabled HT is enabled. I tested 4.2Ghz (21x200) but it required a disappointingly high voltage of 1.42 and temperatures went up to 65C. I think I will stay at this frequency and try to lower voltages as much as possible.

 

[ssnyder28]

You should be fine as long as youre staying under 70C. What kind of cooling are you using?

 

[Brackle]

You should be fine as long as youre staying under 70C. What kind of cooling are you using?

Using the an Antec 920 with 2 Noctua NF-S12A fans. After testing with IBT on very high my max was 73c.

Yea think I should be good to go for awhile.

 

[primetime]

working on lowering pll today....well see how far if any i can lower it and maintain same speed...going to start off at 2.0 and go from there....thinking i should be able to lower it as far as DASHIT (1.95) idk we shall see
edit: managed to pass a few tests down to around 1.95 pll and ended all the way back up to where i was (2.10) before i had perfect stability...go figure...i either have to live with voltages im using or lower the blck/overclock till i get to a certain point and try again....for now i'll just let it ride and hope for the best...long as temps stay ok and it keeps passing every test...i think i'll keep the overclock

 

[MN Scout]

I'm up in Windows with a BCLK of 180 for 3.96GHz with the x5670. Turbo Off, Speedstepping on, C-states on. Vcore:1.28, QPI: 1.26, Vdimm:1.5

Using UBCD, I ran a handful of stress tests for 12 hours before ever booting into Windows. Still crashed the first time in Windows; at which point I turned Turbo Off.

Currently running IntelBurnTest, I'm seeing max temps of 71C in Real Temp GT. Need to check in on my ram timings - CPU-Z reports 9,10,10,25 for 667MHZ and I'm currently running 9,9,9,24. I may want to relax them... the motherboard wanted to run 8,9,9,24 Edit: The newest CPU-Z shows 9,9,9,24, so I'll just leave it where it is at for now.

Just loading up a few programs, and the browser, I can already tell it is faster. I think this was a good decision to get this processor. Should hold me out till the next reinstall of Windows at which point I'll put in an SSD and it'll really feel like a new computer.

Thanks for the OC suggestions and support.

Edit: My Adobe Premiere CC encodes take 1/2 the time. Lightroom is really snappy now. This is great!

 

[primetime]

I just use AI Overclock Turner for [X.M.P]
Extreme Memory Profile [Profile #1]

to get my ram timings down perfect - just always seemed to work well for me...
If you get board with current overclock you can always try my settings for 4400mhz take your time with it...thats all the fun...i can tell you this mine is 100%stable at the current overclock...i think its just a board thing..since my last chip (5639) needed the exact same settings to be stable as well...Know one in this thread has burned theirs up yet (knock on wood) maybe i be the first lol ..but i hope not hehe ...I am starting to get very high temps running Intel Burn test at max...just a reaction to summer moving in...so i ordered some new past and cleaner...hoping i get a 5 degree drop which is mainly what i need
this is what i ordered:

Im also willing to entertain any other ideas for lowering my max temps as much as possible...might find a way to turn my heat sink and have it facing up toward the top 2000 mm exhaust fan...but i think the fan would block the ram slots if i did that( would need super low profile ram) but it could also get me stable ram at 2000mhz instead of 1600...so still looking for ideas ( and truthfully its all about the money)...i may try to rig up another 120mm fan (since i have plenty spare) on the other side of the 120 ultra for a push pull effect...but i hear this doesn't do much but add noise...could be worth a try

think ill try the new past and cleaner...if that don't work i just lower the clock to 4200mhz as well an see where that gets me...its never overheated to the point of failure or not passing a test but i don't want it to ever do that as well...and its only getting hotter as time goes on...to me thats what gets people damaging there chips and wondering why it quit working

I may also keep entertaining the idea of a custom loop with a 2000 mm radiator to mount on top my huge exhaust fan the top of my case..all in all im still stable and running below tjmax but i prefer to keep it below 80 for safety...actually 70s even better
Her a question for all people here...what software is most trustworthy for monitoring temps...i had been using core temp forever...but i noticed HWMonitor works good as well but it reports a bit lower temps compared to core temp
I may even look into just a newer air cooler even though i love the one i been using and hate spending more and more cash..think ill bring the tower out o the garage and blow it out with the shop vac today...hell my new past should be here tomorrow..and just being clean should help a lot by itself

lol all this talk of heat but it actually chilly outside for a change oh and before i forget...this is my antic 900 in case anyone thinks of ways to drop temps cheaply and easily...course it might just be worth it to spend the money on a custom water loop

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[Zoson]

CoreTemp reads the internal thermal diodes built into your cpu cores.

 

[primetime]

CoreTemp reads the internal thermal diodes built into your cpu cores.

thats what i was afraid off...guess ill ditch HWMonitor PRO at least for accurate CPU temps....no crashes or failures yet..but i got to cool things off before i have a melt down..at least while gaming bf4 it hardly stresses the CPU and never gets above 35 degrees if that.....Zoson ....what you do anything different than what came to mind?

 

[primetime]

Was kind surprised running prime for max heat...and heat wasn't bad at all compared IBT max ram...

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No where near as hot as Intel Burn Test...i think the better past and cleaner will be all i need

 

[ant0ny]

Nice job Prime. Yeah I found the same between IntelBurn and Prime95. What score do you get in CineBench now?

 

[Zoson]

thats what i was afraid off...guess ill ditch HWMonitor PRO at least for accurate CPU temps....no crashes or failures yet..but i got to cool things off before i have a melt down..at least while gaming bf4 it hardly stresses the CPU and never gets above 35 degrees if that.....Zoson ....what you do anything different than what came to mind?

I think you're limited by your cooling. Replacing the TIM might help a little, but really nothing that will help get the temp drop you need. I'd lower your voltage and clockspeed. You might find you can drop vCore significantly at 4.2ghz.

The custom 200mm rad loop is a good idea if you really want to stay at 4.4/go higher. If you can spend a little more on the CPU block, you should consider the swiftech apogee drive 2. It uses an MCP35x as the pump, and a base that's just a lightly modified version of their high-end block. $20 also gets you an MCRes micro(the little box res in my system).

 

[ant0ny]

I think you're limited by your cooling. Replacing the TIM might help a little, but really nothing that will help get the temp drop you need. I'd lower your voltage and clockspeed. You might find you can drop vCore significantly at 4.2ghz.

The custom 200mm rad loop is a good idea if you really want to stay at 4.4/go higher. If you can spend a little more on the CPU block, you should consider the swiftech apogee drive 2. It uses an MCP35x as the pump, and a base that's just a lightly modified version of their high-end block. $20 also gets you an MCRes micro(the little box res in my system).

On my MB the x5670 @ 4.2GHz I just run everything on Auto and everything turned on... which I think is pretty much what Prime was getting as well. I too had heating problems with the H90 cpu cooler but it wasn't too bad I just want my system to go as fast without noise which @ 4.2 it is.

On an interesting idea... have you heard of anyone stacking cpu coolers? I spoke to some guy who said he saw 2 water cooling blocks stacked... the first one was obviosly a hand made block but an interesting idea though.

I have seen a water block that had 2 water paths through it and ran 2 seperate water pumps at the Uni many years ago and again all hand made.

 

[Brackle]

On my MB the x5670 @ 4.2GHz I just run everything on Auto and everything turned on... which I think is pretty much what Prime was getting as well. I too had heating problems with the H90 cpu cooler but it wasn't too bad I just want my system to go as fast without noise which @ 4.2 it is.

On an interesting idea... have you heard of anyone stacking cpu coolers? I spoke to some guy who said he saw 2 water cooling blocks stacked... the first one was obviosly a hand made block but an interesting idea though.

I have seen a water block that had 2 water paths through it and ran 2 seperate water pumps at the Uni many years ago and again all hand made.

Interesting. Not sure why you having heat problem with the H90. You running 1 or 2 fans?

I have an Antec 920, keeping my X5650 around 81c after 3 hours of prime95.

Not sure how stacked water blocks would go, although I think that would be pretty cool to see. I have thought about going WC with my setup, Just not sure I want to spend the money to get it all going.....lots of money