My brother just installed a system with that MB and has been having trouble for about a month getting Vista64 to work with 8GB of Corsair RAM (4 sticks of 2GB each). His specs are somewhat similar to my new system:
OPERATING SYSTEM: now Windows 7 64-bit
CPU: Intel Core2Duo E8600 Wolfdale
MB: Gigabyte GA-EP45-UD3P
HS: Intel stock sink and fan
RAM: Corsair 4GB(2x2GB) 240-pin DDR2 SDRAM 1066 (PC2 8500) TWIN2X4096-8500C5 (he has 2 sets of these for a total of 8GB he wants to run with Vista64bit) >> there is a possibility that this ram is actually PC2 6400 (comes up like this in CPU-Z)
VIDEO CARD: ATI Radeon X600 Pro (newer video card is now ATI Radeon HD 5450; dual monitor setup)
PSU: Enermax Infiniti 720W
HD: One (1) Western Digital Black WD1001FALS 1TB 7200rom 32MB cache SATA 3.0GB/s
DVD-ROM: (not sure but it's PATA)
SOUND CARD: RME Hammerfall DSP Multiface (PCI card with firewire connection for outside unit)
Bolded above stuff is for 2013 system!
He's using the F7 bios right now and the system actually did run for 2 or 3 days without problems at one point, but now it's giving him fits again. It seems his RAM will work in slots 2 and 4 no problem but not 1 and 3 and all 4 slots filled won't work either (for what it's worth, a single stick in slot 2 worked and same for slot 4; single stick did not work in slot 1 or 3). He loads fail-safe and optimized defaults (and also changes DRAM voltage to 2.1V as suggested for this Corsair RAM) and the same thing. Anyone have a similar system running with all 4 slots filled (8GB RAM) with Vista 64-bit? He is already on his second MB (same EP45-UD3P) but it's looking like he may have to RMA again. I wonder if he flashed back to F6 bios or forward to F9 if that would do anything (maybe F7 messes with RAM slot access or something on this particular board).
Vista64 does recognize the RAM as 8GB and he can get into Vista64 for a little while with all 4 slots filled, but he runs the Vista memory testing program thing and it says he has hardware problems. We now have the timings set to SPD of 5-7-7-24 and I also told him to clock the memory down from 333 to 266 with one of the bios settings (forgot which one though) and that helps a little but not much. His problem is getting it to post and the screen will start to come up and then reboot and sometimes he'll get into Vista, but then he'll start having problems again and especially if he has to reboot for some reason.
I decided to do some searches the other night and with this search in google "P45 mothreboards Vista 8GB RAM" I found some interesting links that suggested some P45 motherboards have trouble with all 4 slots filled in Vista64 and that some Gigabyte boards may just not like Corsair RAM with all 4 slots filled.
He's finally testing his memory using memtest86+ and so far he's tried one memory stick in slots 1, 2 and 3 (possibly slots 0, 1, 2 on board; but let's call them 1-4 for this thread; he hasn't tested that same stick in slot 4 yet). The test results are fine for slots 1 and 2, but he gets errors in slot 3. Does this mean slot 3 is toast on this MB or just that this stick doesn't like slot 3? I told him to try same stick in slot 4 and then the other 3 sticks in slot 3 and then finish the tests with the other 3 sticks in slot 1. He'll be doing that tomorrow.
I'm guessing if the first stick in fine in slot 4, then it just doesn't like slot 3 or the MB slot 3 is bad. If the other 3 sticks test fine in slot 3, then slot 3 might be fine but that one stick is bad. If the other 3 sticks test fine in slot 1 also, then maybe all sticks are fine.
1st memory stick: slots 1,2,4 work; errors in slot 3
2nd memory stick: slot 3 works, errors in slot 1
- I know this doesn't mean much for memtest, but he tried these two sticks in the working slots in dual mode (slots 1 and 3) and got errors based on the RAM GB position showing in slot 3.
- before this he tried just putting the other two sticks in slots 2 and 4 and hoping for a miracle posting to Vista64 and it posted OK, but he got hardware errors with Vista's memory testing thing. So, even though the 1st stick works individually in slot 1 and the 2nd stick works individually in slot 3, they don't play well together.
- he's now trying the 2nd stick individually in slot 2 and then slot 4 to complete the memtest tests for these two sticks and will continue with the 3rd and 4th sticks tomorrow.
My guess is if all sticks test fine in slots 2 and 4, then the memory is fine and his MB is screwed up (slot 3 a lot and slot 1 a little). I'm still wondering if flashing the bios to F6 or F9 would do anything though. One more thing: is there any way to get another MB without paying more $ that likes to run with Corsair, Vista64 with all 4 slots filled (8GB total)? In other words, should he RMA a second time or try another MB altogether? Any other ideas? Thank you.