Diamond 7850pe52g, Shocker under the hood!

[RigRebel]

Hello all,

Recently I became the proud new owner of a Diamond 7850pe52g http://www.diamondmm.com/7850PE52G.php (awwwwww) ...

Like many, I can report that this beautiful and short 7850 is a great little over-clocker (especially with aftermarket cooling as some report) and a nice little bang for the buck. Currently I've got it on full maxed CCC over clock with 1050Mhz Core/1450Mhz Memory and 20% over-volting on it and it's purring like a kitten with no hiccups. The over clocking gained me a 15% higher score in 3D Mark 2011 vs. stock clocks and 11FPS total in Furmark at 1920x1080 burn in. I was very impressed with the free boost with just a flick of the slider in CCC Overdrive. However, read on...

Like many I've discovered she can run a bit toasty with V-sync off and full over clock. Considering she has a radial fan similar, but smaller to the MSI R6850, I find it surprising that I'm seeing heat at 93*C at full OC with full load. Radial fans traditionally provide a much better cooling option than the big inline fin blocks popular to the GTX series IMO so why is she kicking up so much heat? I didn't think it to be the heat sink because again, it's a nice radial heat sink much like the R6850 and that one does 71*C full over clock at 960Mhz. So, I thought possibly it could be the Thermal Paste. I decided to take it apart and the answer was kind of shocking.

I was surprised to find out that the factory thermal compound used appeared to actually be of very good quality. It is a silverite compound much Arctic Silver and not the cheap gray clay used on many OEM computers like Dell and HP. In fact the thermal compound had a similar look, feel, pliability and consistency as Arctic Silver. So if it wasn't the heat sink what was it...? Alas, The culprit IS a horribly rough copper heat plate!See attached pictures! It's been machined flat but you can see the saw blade grooves all in it radiating out like a thumb print! Someone made the decision to skimp, well toss out entirely, the idea of providing a mirror finish to the plate. I've never seen a plate like this in person only in pictures. This thing is rough and has more ridges in it than a Ruffles wavy potato chip! lol I've been out of the lapping game for awhile so I'm not sure if this is the "new and improved" way of producing a heat sink copper plate but where I come from it's just horrid... pictures attached.

I Wonder, should I bother to lap it or does it have just too rough of a surface to get it smooth before losing to much cooper for it to even touch the GPU? I'm afraid if I try to lap it with that rough of a finish on it, I could wear it down too much beyond use and possibly even kill the flat edge.

Thoughts?

My final thoughts: I'm really kind of disappointed in this discovery... sure it's still a "good card" and getting me the FPS I want; but, someone obviously decided to skimp and cheap out on good "quality" practices for fit and finish that has directly lowered the cooling solution of the product and in fact cheapened the product... It could have been such a better cooler but some bean counter had to say no to the quality fit and mirror finish. It's obvious that someone decided to cheat the public a little and skimp out on a good finish because who's going to take it apart and see the heat plate right ?
Well I did... And, I for one feel kind of duped!

I was going to to get a second one for Xfire, I may rethink that now
Ps. Power color has an identical model, I wonder if theirs is the same. I'd report this to Diamond but they'd probably void my warranty for taking off the heat sink
Just reply > "sucks to be you" lolz

[OneCool]

Lap it!!

400grit
1500grit
metal polish


Keep it flat!!!!

[RigRebel]

Originally Posted by OneCool

Lap it!!

400grit
1500grit
metal polish


Keep it flat!!!!

I don't know if you can tell by the picture but this thing has like a 1nanometer raised edge where the GPU would make contact...It may look higher with the residual thermal compound but it's not, I'm pretty sure to get the grooves out It would go all the way to main cooper plate lvl. The raised ridge is only on 3 sides then trails to the bottom screws if you're looking at the left picture. Plus with the screw holes on the sink it's not gonna be pretty around there. I've lapped before and I'm sooooo temped but there's not much platform there... Don't want to f-it up and loose warranty. I still have 30 days to return.... It would suck to ruin a brand new $280.00 card lolz that I could have returned.

HOWEVER it would be a fun epic project if I could turn it around by lapping and get 5-10*C lower ... spidey sense is tingling though lol.

[Meaker]

That card is screaming out for a zalman heatsink, the zalman GV1000 would look awesome and let you clock it to hell and back.

[Mussels]

agreed, i'd attempt to lap it, and if that failed, replace the heatsink with third party.

[DarkOCean]

I would definitely lap it.

[Kenshai]

Lapping it will only give a few degrees difference. Likely won't change max overclocks.

On the other hand, your case is quite small and you would likely see a difference in temperature by improving air flow or moving to a larger case.

[lilhasselhoffer]

Returning the card would do nothing.

The fact that such a rough finish is there is obviously a manufacturing choice. Smoother finishes require substantially more work, or skilled laborers. To alleviate this problem you'll have to take action yourself.


That said, you've done 99% of the job, why not just replace the cooler with something aftermarket? You won't have to worry about anything, and you might even get a little more performance.

[RigRebel]

Originally Posted by Meaker

That card is screaming out for a zalman heatsink, the zalman GV1000 would look awesome and let you clock it to hell and back.

I looked into that and that is a beautiful heatsink! It's probably low enough to still work great in Xfire with a second card...The only issues are that 1. the heatpipes would probably hit the 200mm fan in the vulcan case and 2. This card may eventually end up in an Aerocool QX-2000 cube case I have as an HTPC build when GK110 comes out and I know it won't fit with those extended heat pipes. Also, I agree with the hell and back overclocking this would allow since some people are reporting 1350Mhz OC core with Powercolor's identical twin to this card and aftermarket cooling. All the parts are not in the case yet because IB heats up and 1155 will be dead in April so not sure I want to mod because not married to the overall build yet.

Originally Posted by lilhasselhoffer

Returning the card would do nothing.

Well Store manager will let me return for complete refund under 30 days. I still have plenty of time. I can get my cash and wait for the GTX 660 TI which is what I originally wanted but just got antsy because of D3 launch. But the quandry is if the GTX 660 TI is sticking with 24 ROPs and 192bit could be a lateral if not slight down grade from the 7850s 32Rops and 256bit. Thus the delima. Might I add this is a sucky time all around to be buying upgrades. IB heats up, x79 won't fully support PCI-E 3.0, 1155 will be dead next year. GTX 660 Ti taking forever! Again, sucky time to purchase upgrades

Originally Posted by lilhasselhoffer

The fact that such a rough finish is there is obviously a manufacturing choice. Smoother finishes require substantially more work, or skilled laborers. To alleviate this problem you'll have to take action yourself.

So true, I also think this is 100% the choice/fault of the manufacturer skimping out to save a penny because 1. average users aren't going to look under the heatsink because voids warranty and 2. you can see this is caused by the blade edge when machined.This is normal for most manufacturing processes but not as a final product. Most manufacturers will polish this out. Why Diamond didn't is beyond me and dissappointing
. Who knows, this could be a parent company that makes it with Diamond's name on it because Powercolor has an identical model. Either way it fails as a properly finished heatsink IMO and dissappoints me as a customer. I'd LOVE to approach Diamond on it and see it changed but 1. I'm worried they'd say "You looked under the heat sink ? Sorry, you voided your warranty have a nice day" or 2. just give me a refurbed model with other issues.

Originally Posted by lilhasselhoffer

That said, you've done 99% of the job, why not just replace the cooler with something aftermarket? You won't have to worry about anything, and you might even get a little more performance.

I'd love to replace with an aftermarket cooler but if I do that I'm sure I'll take up Xfire space on a smaller mATX board inside the Vulcan NZXT case. Also again, it's still under stores full return policy so won't put me out much other than time to get a diff card. And won't have to buy an aftermarket cooler and take up xfire space. Would be a fun project though but since it's still in full return window I think I'll make it someone elses problem especially since Diamond shouldn't be peddling crappy rough heatsinks like this anyways.

To address some other suggestions 1. thank you for responding . 2. Kenshai > as far as lapping I agree with you. I doubt I can expect more than a couple of degrees and really this thing is so rough I'd have to lap it from here to tuesday if I just go by heatsink preasure. I'd really have to take a lot off the pictures don't do this justice.
3. The case has pretty decent cooling, I have the optional 200mm side fan blowing right on it but that does disperse to the edges.

Idk, I agree with a lot being said and had this been an old card I had for a couple years yea OR if it was sooo awesome on performance I just couldn't part with it then; yea, I'd not think twice to lap it and stick a cooler on it. But, the card still within the 30 day window for retail returns and the market is 3 months from 660 TI possibly and GTX 660 is rumored to launch on June 25 now. I think I'll throw this fish back and try again with the 660 or 660 TI. Sucks though would have been fun to mod.

Thanks for all the replies.

[theoneandonlymrk]

Originally Posted by lilhasselhoffer

The fact that such a rough finish is there is obviously a manufacturing choice. Smoother finishes require substantially more work, or skilled laborers. To alleviate this problem you'll have to take action yourself.

probably they are not assed, but the guy who machined that wants a slap, as his tool needs sharpening and he needs to slow down the cutting travel speed a fair bit, you can get an acceptable machined finish this way and i have many timeth, just less machined units per hour

dont be scared lapp itt, you know ya wana, and you may gain more then just a few ,a processor or HSF block lapping does admittedly net 5-10 degrees max but thats starting from an allready okísh starting point, thats machined very poor so the gain might be marked.

[RigRebel]

Originally Posted by theoneandonlymrk

probably they are not assed, but the guy who machined that wants a slap, as his tool needs sharpening and he needs to slow down the cutting travel speed a fair bit, you can get an acceptable machined finish this way and i have many timeth, just less machined units per hour

dont be scared lapp itt, you know ya wana, and you may gain more then just a few ,a processor or HSF block lapping does admittedly net 5-10 degrees max but thats starting from an allready okísh starting point, thats machined very poor so the gain might be marked.

lolz yea you know I do want to lap it I’m just trying to think responsibly since I have never intentionally voided a warranty before especially on a card barely 2 weeks olds so ya one toe in the water atm. I could easily return it but the mod would be fun and epic if I could get this little card to under 60C and break the Overdrive ceiling and push it past 1300 MHz!! (Tim Taylor grunts uhhh uhhh uhhh)
One thing I'm concerned about in lapping is the little ledge that is on the main copper block. Look at the picture for me and see if that's gonna be a problem if I lap it to much and kill that ledge. It's in the pictures.
Can someone comment on that ledge please and tell me what will happen if that ends up flat and even with the rest of the block ? Will the heatsink still make GPU contact ? I think so cause the backplate is springed with rubber grommets but not 100% sure.

HOLD the phone!
I think this might be possibility also and it looks cool heck...
http://www.arctic.ac/en/p/cooling/vg...us.html?c=2182

Anyone ever try this mono cooler from Arctic? Anyone use it in Xfire with 2 cards? It may be worth a shot.

[erocker]

Only info I've seen on how well the MONO works was on a GTX 680 and the results weren't very good. There are definitely better coolers out there at that price. It also takes up more than two slots.

[RigRebel]

Originally Posted by erocker

Only info I've seen on how well the MONO works was on a GTX 680 and the results weren't very good. There are definitely better coolers out there at that price. It also takes up more than two slots.

Thanks Erocker! to the rescue on question as always. props.

Sorry miss read you so reposting. More than double slots ? Well that's out then. My main concern is how thick the aftermarket cooler/fan setup is gonna be because I still want room for a second card to xfire with.
Any other cooler suggestions ? Here's the card again for referrence http://www.diamondmm.com/7850PE52G.php


Guys I'll welcome cooler suggestions

[erocker]

I used one of these before and it was a great cooler. The newest revision works with your card: http://www.gelidsolutions.com/produc...1&cid=17&id=52

I wonder if this would fit? http://www.zalman.com/ENG/product/Pr...ad.asp?idx=385

There's also this: ARCTIC COOLING ACCEL-TT II Fluid Dynamic Accelero ... ~ kinda ugly and bulky though IMO.

[RigRebel]

Originally Posted by erocker

I used one of these before and it was a great cooler. The newest revision works with your card: http://www.gelidsolutions.com/produc...1&cid=17&id=52

I wonder if this would fit? http://www.zalman.com/ENG/product/Pr...ad.asp?idx=385

That gelid is purty ... at 216cm lenght it's 8.89 inches if my math is correct.

OHHHHH now that Zalman is gorgeous... that would look sick on a Maximus Gene z77 or x79 rampage board.

UPDATE... ding ding that Artic looks perfect!

[erocker]

The Zalmann is probably the best performer out of the bunch too. If you want better than that, I think the next step up would the the Accellero Xtreme series. I'm just not sure if it supports the 7850.

[RigRebel]

Originally Posted by erocker

The Zalmann is probably the best performer out of the bunch too. If you want better than that, I think the next step up would the the Accellero Xtreme series. I'm just not sure if it supports the 7850.

User of the ACC TT II on a powercolor identical twin card to this one reports this > "Monster Overclocks are Availabe with some minor mods. I replaced my stock coller with an Accelero Twin Turbo II, and then flashed the BIOS to an ASUS DCU TOP Edition which unlocks voltages up to 1.3v. The increased voltages and GREATLY increase cooling performance now enable me to clock the GPU to to 1350MHz stable (yes 1350MHz) @ 1.3v and bench upto 1385MHz. These speeds murder a stock 7950 and equal a 7970 within most benchmarks.

That's a 60% overclock on air, and within a Micro-ATX case with. Just Google "7850 1376MHz" and you will find my benchmarks."

Qouted from 555Buk on Newegg.com PowerColor AX7850 2GBD5-2DH Radeon HD 7850 2GB 256...

Update: thought. I'd have to see if the ACC TT II will get in the way of the Xfire bridge. The ACC TT II Says it's 53mm high (roughly 2.18 inches) but the diamond is only 1.5 and that even looks a little to tall for xfire. hard to tell current board is only single pci. Waiting to get newer board if IB gets solved or haswell comes sooner but will probably be later

any good links for how to take the intergrated heatsink off a i5 3570k ?

UPDATE: Well I made my choice and shipped it back. With the 660 TI not even out yet and pressumably right around the corner, because 660M Moblies are already being sold in ASUS laptops, I decided to ship the Diamond back and get my $. I'll try again in a couple of months with either a 600 series or a better 7850.
Peace