Overclocking HIS 3870x2

[stonedzen]

Hello all.

I just overclocked my Phenom II x4 955 BE to 3.8ghz on stock voltage. Now, my video card seems to be bottle necking my system. Anyone here running an overclocked 3870x2 ?

I'd love to hear any advice on OCing Ati video cards. I've heard of people OCing the 3870x2 to 940mhz on the cores and 1000mhz on the memory. Every time I aim for even 850mhz on the cores and 950mhz on the memory, my system locks and reboots. Any ideas or suggestions? Thanks!

 

[nforce4max]

The 3870x2 isn't the most overclockible card out there due to the varm and cooling. You should just start with either the cores or the vram alone to poke and prod for the limits of your card. By the way tell me how well this card scales in most games since I am interested in tracking down one for trifire?

 

[stonedzen]

Does quite well in games. With my new system I'm getting very good fps in Modern Warfare 2 with 2xAA 16xAF on 1680x1050. Handles Napoleon TW pretty well too. Left for Dead 2, runs everything with decent fps. I love the card.

 

[nforce4max]

Do you play wow or multiple accounts at once? I have been wanting one of these lol. Did get a dirt cheap 8800gtx for $32 that turned out to be working.

Try the core alone while leaving the vram as is. How are your temps?

 

[stonedzen]

36-40 idle, 60 max under load. I have a custom fan cycle in rivatuner, so it adjusts with my temps.

 

[nforce4max]

OK those temps are good, how hot are the vrms are getting? Also how are your volts on the 12v rails?

 

[stonedzen]

how do I check vram temps? Neither HWmonitor or rivatuner seem to be able to monitor those temps.

+12v on HWmonitor is reading 12.32 V

 

[stonedzen]

I experimented a lot last night with no luck. Increasing the vram speed causes near instant crash, no matter how small the increase. Whenever I increase the Gpu cores, the second core always drops to default speed after a few mins while the first core stays overclocked.

FOR example:

Core 1: 860mhz, Core 2: 824.5mhz, Vram: 900mhz

The single core overclock appears to be stable, but sees no performance increase. In fact, it seems to hurt performance in games. Basic test in 3DMark06 is scoring around 18800. This score jumped to 19500 last night when I increased cpu OC to 4.0ghz on 1.5v. However, as said before the gpu ocing sees no increase in benchmarks. Any other ideas?

btw, im using rivatuner to monitor and AMD GPU Clock Tool to adjust speeds.

 

[nforce4max]

VRM: power stages

The voltage is good and should be getting higher clocks than what you are getting now. If you are unable to get any thing higher then start looking at crossfirex. A single 3870 or another 3870x2 might be the boost you are looking for.

 

[stonedzen]

yeah i've thought about it, maybe running two 3870x2s. Can find them cheapish used...

http://cgi.ebay.com/VisionTek-HD-3870-1-GB-GDDR3-Graphics-Gaming-Video-Card-/270582058972?cmd=ViewItem&pt=PCC_Video_TV_Cards&hash=item3efff28fdc

 

[nforce4max]

yeah i've thought about it, maybe running two 3870x2s. Can find them cheapish used...

http://cgi.ebay.com/VisionTek-HD-3870-1-GB-GDDR3-Graphics-Gaming-Video-Card-/270582058972?cmd=ViewItem&pt=PCC_Video_TV_Cards&hash=item3efff28fdc

I have been watching that auction for the past few days. For me I am broke thanks to the sh^t economy.

 

[stonedzen]

yeah me too. realistically Ill probably go $70 for a 3870 on amazon, after I save some cash. that way I can do a 3-way crossfire x. Seems to be most affordable and least dangerous way to get a performance boost out of my system. Also thinking about getting win7 64-bit so I can use all 4gb of my ram is the OS.

btw, I used rivatuner to OC both cores to 850mhz stable, w/ no OC on the memory. didnt see any increase in 3DMark06 (stayed around 19400) and my cpu and gpu cores were running dangerously hot.

I've decided not to attempt any more overclocking on this card, as I am not seeing any benefits and the risk is too great. I also dropped my cpu back to stock voltage and a 3.8ghz OC instead of 4.0ghz. Dropped my temps over 10 degrees. CPU was running 64 C peak during 3Dmarks cpu test. Scary!

Now its back down to mid 30s idle and low-mid 40s load, and still got a 600mhz increase over stock clock.

 

[firebird]

I recently swapped out my CrossfireX 3870's (Visiontek 3870 OC and ATI 3870X2) for my 5850. I have them lying around in the basement if anyone is interested.

The 3870X2 was modified by me with heat sinks on all power circuits and memory, as well as the ZEROTherm coolers on the GPUs. The Visiontek came with the same ZEROTherm cooler.

I have the 3870X2 taken aprt right now (no cooling or sinks), but it's working and I have all the original sinks, fan, shroud and box even.

I used to run all 3 GPUS @ 850 and memory on the X2 @955.

GPUs wouldn't go higher than 860 without issues, and I maxed out the memory @955 on the X2 (high as Overdrive would go).

 

[firebird]

Thought I'd post this as well: http://www.flickr.com/photos/maudite/sets/72157605024948882/ if anyone cares to see what the mod was.

 

[nforce4max]

I recently swapped out my CrossfireX 3870's (Visiontek 3870 OC and ATI 3870X2) for my 5850. I have them lying around in the basement if anyone is interested.

The 3870X2 was modified by me with heat sinks on all power circuits and memory, as well as the ZEROTherm coolers on the GPUs. The Visiontek came with the same ZEROTherm cooler.

I have the 3870X2 taken aprt right now (no cooling or sinks), but it's working and I have all the original sinks, fan, shroud and box even.

I used to run all 3 GPUS @ 850 and memory on the X2 @955.

GPUs wouldn't go higher than 860 without issues, and I maxed out the memory @955 on the X2 (high as Overdrive would go).

Nice work, sigh I am broke right now but I have every thing needed for trifire except for the 3870x2. If I had the money I wouldn't mind it being stock at all just so long it works and has the pads. Don't want to cook the VRMs. I got a very roomy but ancient case.

http://img260.imageshack.us/f/img260/7796/pict0023w.jpg

Ugly but roomy plus I try to keep every thing cool.

 

[stonedzen]

I recently swapped out my CrossfireX 3870's (Visiontek 3870 OC and ATI 3870X2) for my 5850. I have them lying around in the basement if anyone is interested.

The 3870X2 was modified by me with heat sinks on all power circuits and memory, as well as the ZEROTherm coolers on the GPUs. The Visiontek came with the same ZEROTherm cooler.

I have the 3870X2 taken aprt right now (no cooling or sinks), but it's working and I have all the original sinks, fan, shroud and box even.

I used to run all 3 GPUS @ 850 and memory on the X2 @955.

GPUs wouldn't go higher than 860 without issues, and I maxed out the memory @955 on the X2 (high as Overdrive would go).

How much you asking for each card individually? I may be very interested in one of the cards. Which one depends on whether my PSU can handle a second x2. I kind of doubt it. I have a Rosewill RS-500 seen here: http://www.newegg.com/Product/Product.aspx?Item=N82E16817171031

Not positive this PSU can even handle trifire. Any input?

 

[firebird]

I'm using a Silverstone 750 watt PS (18 amp 12v I think) and under tri-fire I could make my 600 watt UPS reach it's limit and shut off when playing a few games.

Most of the time while gaming the system was pulling between 490 and 550 watts with 5 HDDs and a over clocked core2 Quad.

I will sell either of the cards, we can talk via PM or email about cost.

Personally I think the Visiontek card is great. I can't remember exactly what the stock clocks were (775 maybe?) but it could handle 860 on the core and still run around 70 degrees max in my case.

The X2 is good too, but it's such a heat generator that even with the modded cooling you need go have really good ventilation to remove the heat from the case or temps will climb back up. The ZEROTherm fans also take care of the need for another tool to work with fans as they speed up with increased temp automatically.

 

[stonedzen]

I'm using a Silverstone 750 watt PS (18 amp 12v I think) and under tri-fire I could make my 600 watt UPS reach it's limit and shut off when playing a few games.

Most of the time while gaming the system was pulling between 490 and 550 watts with 5 HDDs and a over clocked core2 Quad.

I will sell either of the cards, we can talk via PM or email about cost.

Personally I think the Visiontek card is great. I can't remember exactly what the stock clocks were (775 maybe?) but it could handle 860 on the core and still run around 70 degrees max in my case.

The X2 is good too, but it's such a heat generator that even with the modded cooling you need go have really good ventilation to remove the heat from the case or temps will climb back up. The ZEROTherm fans also take care of the need for another tool to work with fans as they speed up with increased temp automatically.

PMed