4870 Crossfire Reboots in Crysis Warhead (Power problem?)

TLDR version:
http://www.newegg.com/Product/Product.aspx?Item=N82E16817171023 usable for 4870 Crossfire or does it really suck that bad? Would having fans hooked inline with my molex to PCI-E power converters cause me issues with Crysis Warhead rebooting my machine?

First, my rig:
Gigabyte EP45-DS3R Mobo
4 GB G.Skill DDR2 @ 400 mhz
E8400 @ 400 mhz x 9, 1.3v loaded
2 x Diamond 4870 @ 780/1080
2 x 36 GB Raptor HDD RAID 0
1 x 750 GB Maxtor HDD
5 x 80 mm case fans (36 cfm)

So there are things I am going to do when I get home to test further, but I wanted to get some input beforehand.

I recently upgraded and added another Radeon 4870 so I can run a Crossfire setup. Back when I got my first 4870, I realized my new card didn't come with an adapter for PCI-E power connectors, so I said screw it and bought a new PS. You can find it here:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817171023

Long story short, it is a 650W 80Plus unit from CoolerMaster, with 3 19A 12V rails. It is nicer than their standard 650W unit. It was the only one Fry's had in my price range and even then I got gouged, but I figured what the heck it'll be good for adding another card. To me, considering that

a. my system pulls about 480 - 500 watts based on this calculator: http://extreme.outervision.com/psucalculatorlite.jsp
b. ATI and most manufacturers assume people buy horrible power supplies, so they suggest 750 watt PSes for Crossfire because most people's PSes suck
c. TF2 plays for hours with no issues

I shouldn't be having problems. Soooooo, now to my main issue. I've only had this setup for two days, and at first it played games flawlessly. Well, last night I was playing Crysis Warhead and twice, after about an hour of play, my computer just reboots itself. No errors, no blue screens (I have the computer set to not automatically restart on errors), nothing. It just reboots and loads Windows up like I had just turned it on. Naturally my first inclination is to lean towards this being a power issue, but would it just kill my system like that? Instead of just dropping me back to the desktop or something? Now years of experience tells me that power issues can cause all kinds of whacked out things to occur, so I won't be surprised if this is the case, but it really seems like my PS should be okay, no? It isn't a Corsair or a PC Power and Cooling, but it isn't a POWMAX either.

I haven't tried lowering the clock speeds of my cards, but running a few loops of Vantage or playing TF2 or the new Warhammer MMO don't phase it. However, Warhead is certainly more demanding than than Warhammer/TF2, but not Vantage, right? Those two I'd think would be equal. My old card was good past 800/1100 but one thing I'm gonna try is going back to stock clocks on both cards.

Now, something else worth mentioning: My PS has two PCI-E power connectors. So as it stands, I have one of each of the two plugged into one card, and then I use two PCI-E converters plugged into four molex connectors for the other two PCI-E power connections. Now, I only get 5 molex connectors, so due to wiring issues each converter is also plugged into two fans. Is it possible that Crysis is just so demanding that it is pwning my power supply by proxy of these fans being hooked up inline with my video cards? If it comes down to it, I'll just go buy an extender cable and plug all four fans into one molex line, and the extender cables are only a few bucks, but is that even worth trying?

Any insight is of course much appreciated.

I'm not sure, but i think those 4870's are drawing more power than what the psu can deliver.

Only way to actually find out if it's the psu, is to check it under load with a DMM.

19A x 3 is 57A total, if that's what CoolerMaster claims your psu delivers which is more than enough, but the constant reboots leans towards a weak psu. Could also be a defective unit.

How are the cpu/video card temps?

Temps are doing good, I think. Fan speeds are manually set to 50 percent for each card. Loaded temps are in the 65-70 degrees C range, and I replaced the stock TIM with some AS3. CPU hovers around 48-55 degrees C.

How would I go about testing with my multimeter? I've used it to diagnose bad (i.e. dead) power supplies but really that's about it.

I'm hoping I can go home and re-wire my baby so that I don't have anything hooked up to the PCI-E power converters besides the video cards, and that'll fix my issue. Doubtful but I'm hopeful, lol. Is it possible that power spikes on the lines, or perhaps crappy molex connectors on the fans have something to do with it at all? (I'm really fishing for that to be true but I really have no idea. I do know that the more things you hook into a series the more resistance you get....but I'm a CompSci grad not a CompEngy so electricity is not my strong suit).

Temps look pretty normal. To check the psu with a DMM, check out this guide . If you're getting power spikes, then that psu is defective and should be replaced asap, otherwise it'll fry something. I would'nt trust it.

Thanks for the DMM link. I hadn't hit the power supply threads yet.

After looking over there (PS forums), it sounds like my assumptions are spot on.

http://www.ocforums.com/showthread.php?t=548862

"3 x 12V rails
A "modified" ATX12V specification that takes into consideration PCIe power connectors.
One rail to the CPU, one rail to everything else but the PCIe connectors and a third rail just for PCIe connectors.
Works perfectly for SLI, but not good for PC's requiring four PCIe connectors."

"An FSP Epsilon 700W has ample power for any SLI rig out there, right? But the unit only comes with two PCIe connectors. The two PCIe connectors on the unit are each on their own +12V rail. Each of these rails provides up to 18A which is almost three times more than what a 6-pin PCIe power connector is designed to deliver! What if I want to run a pair of GTX cards? It would have been ideal if they could put two PCIe connectors on each of those rails instead of just one, but instead those with GTX SLI are forced to use Molex to PCIe adapters. Here comes the problem: When you use the Molex to PCIe adapters, you have now added the load from graphics cards onto the rail that's also supplying power to all of your hard drives, optical drives, fans, CCFL's, water pump.. you name it. Suddenly, during a game, the PC shuts down completely. "

"The only "problem" the occurs with multiple +12V rails is that when a +12V rail is overloaded (for example: more than 20A is being demanded from a rail set to only deliver up to 20A), the PSU shuts down. Since there are no "limits" on single +12V rail PSU's, you can not overload the rails and cause them to shut down..... unless you're using a "too-small" PSU in the first place. Single +12V rails do not have better voltage regulation, do not have better ripple filtering, etc. unless the PSU is better to begin with. "

Silly ATI and their needing two PCI-E power connectors.....

You need to uncheck "Automatically restart" in the control panel to see what error you're getting.

RJARRRPCGP said:

You need to uncheck "Automatically restart" in the control panel to see what error you're getting.

Click to expand...

That is already set. I got an IRQL_LESS_THAN or something similar blue screen the other day that stopped properly, i.e. it didn't reboot. The computer just reboots itself with no blue screen/error.

If I can't get anything out of re-wiring my setup, which is what I guess is going to be the case, maybe I'll switch to 4850's instead. Can't take the PS back since it's past the 30 day return period If anyone is in the market for a barely used 4870, let me know :-D

Would one 4870, 4 80 mm fans, and 3 hard drives even really come close to pulling 19 amps? Maybe I can ghetto rig a battery up to my fans, lol

Would I have this problem (overloading rails) with a 4870x2, since I'll still need some type of converter/adapter for the 8-pin connector (only have two 6 pin connectors built-in)?

Look in gpu-z to see how many amps it uses.

Or when it reboots or even when in operation. How many lights on the card are lit, and if you can tell us which ones. That will narrow down the issue. Expecially since I think it lights up if theres a voltage problem on the cores.

DEZMOND said:

Look in gpu-z to see how many amps it uses.

Click to expand...

Heh so in GPU-Z ver. 0.2.8, VDDC Current jumps from about 25 amps idle to about 50 amps loaded, with a single card....

That doesn't sound right unless that's full system load. In which case....damn.

In regards to the lights well I guess I'll fire up some 3d app and see if I can crash this beast. I forgot those things were on there.

/contemplating taking the 4870 back and picking up a 4850

korruptedONE said:

Heh so in GPU-Z ver. 0.2.8, VDDC Current jumps from about 25 amps idle to about 50 amps loaded, with a single card....

That doesn't sound right unless that's full system load. In which case....damn.

In regards to the lights well I guess I'll fire up some 3d app and see if I can crash this beast. I forgot those things were on there.

/contemplating taking the 4870 back and picking up a 4850

Click to expand...

No thats probably not totally correct. The amperage you have to take into account is what the card is using at X voltage. Which probably is VCore im guessing, which in turn would put the GPU at 63.1W which seems low for a card that chews up a bit mroe than that.

Heh so yah again my electrical nubness shows....forgot about needing to take voltage into account for that amperage reading.

But yeah, I am not buying the info from GPU-Z in regards to that reading.

I did some re-wiring and while I didn't get reboots, I did get a blue screen, but only once. However, I am probably gonna take the 2nd 4870 back. I recall reading that the 2nd card in a Crossfire setup doesn't see full load; is this true? If so, that would mean, not even on full load, it was killing my third 12V rail. So if/when that usage goes up through a new game or driver or what have you, the problem could creep back up again until I get a new power supply (stupid 3 rails....) which won't be soon since this current one is only a month old.

Does anyone have any benches on a 4870 + 4850 Crossfire setup? I've only found 3dmark scores which I don't really care about; I want fps of games. Would it make more sense to sell my 4870 and get two 4850s or is there any actual advantage to a 4870 + 4850 CF setup over dual 4850s? I could sell my 4870 for $220 or so and pick up dual 4850s for around $330.

korruptedONE said:

That is already set. I got an IRQL_LESS_THAN or something similar blue screen the other day that stopped properly, i.e. it didn't reboot. The computer just reboots itself with no blue screen/error.

If I can't get anything out of re-wiring my setup, which is what I guess is going to be the case, maybe I'll switch to 4850's instead. Can't take the PS back since it's past the 30 day return period If anyone is in the market for a barely used 4870, let me know :-D

Click to expand...

I would check the Vcore. That BSOD usually means an unstable core.

RJARRRPCGP said:

I would check the Vcore. That BSOD usually means an unstable core.

Click to expand...

Yah that was when I was messing with my CPU o/c. Point there was that my system was stopping properly and not auto rebooting on a blue screen.

I could ebay the PS but I don't feel justified in the purchase since I just bought the PS last month, at a far higher price since I just couldn't wait to get a 4870 in the mail with a new PS. I have a bad habit of that.

Granted, I only play at 1680x1050 but I want either dual 4870s, 4850s, or a 4870/4850 combo because it keeps my minimum frames up so much higher. In TF2, for instance, yes I can run it maxed w/ 8x AA, but I play in 24/32 person servers. You get 10 people on screen blowing each other up, and it does dip to below 30 fps. With these 4870s I am running 16x AA and don't drop below 50 fps. I can't handle the dips!! So I'm looking for what's the most cost effective at this point. I went overkill, which was fine as long as I didn't need a new power supply. Now that that may be the case, I'm looking more towards being more refined in my choice, instead of OMG KILL IT WITH MOAR POWER!

Any thoughts on a 4870 + 4850 combo? Bad idear?<---- bad idea; might as well get new PS or switch to 4850s...http://www.overclock.net/hardware-news/369535-hwcanucks-hd4870-hd4850-crossfire-mixed-crossfire.html thanks go to canadia for the link