Crossfire GDDR3 + DDR5 compatibility

[Haelis]

Hi,
I bought a 4850 512mb about 3 months ago. I would like to build this into crossfire but the card is no longer available. A newer version with DD5 instead of GDDR3 is now on sale.
Would these two cards work with each other well? I understand that the more powerful card is generaly lowered to the level of the lesser card for the number of mb and the GPU involved, but Tom's article said nothing about the differences between memory types.

Old card is: SAPPHIRE 100245HDMI Radeon HD 4850 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready CrossFireX Support Video Card
Newer model is: SAPPHIRE 100245DDR5L Radeon HD 4850 512MB 256-bit DDR5 PCI Express 2.0 x16 HDCP Ready CrossFireX Support Video Card

GPU Radeon HD 4850 Radeon HD 4850
Stream Processors 800 800
Memory Size 512MB 512MB
Memory Interface 256-bit 256-bit
Memory Type GDDR3 DDR5

A secondary question would be if I have enough power for crossfire with a 650 watt PSU.


PC specs are:

Intel Core 2 Quad Q9550 Yorkfield 2.83GHz LGA 775 95W Quad-Core
GIGABYTE GA-EP45-UD3P LGA 775 Intel P45 ATX Intel Motherboard
Kingston HyperX 2GB 240-Pin DDR2 SDRAM DDR2 1066
Western Digital Caviar Blue WD6400AAKS 640GB 7200 RPM SATA 3.0Gb
CORSAIR CMPSU-650TX 650W ATX12V / EPS12V SLI Ready CrossFire Ready 80 PLUS Certified Active PFC
+2 older hard drives (80 gig and 200 gig) are inside but these could be removed if power is an issue.

 

[Rustyy117]

Power wouldn't be an issue, I'm pretty sure you can crossfire two cards from the same series but with different GDDR types, But wait for a deffinate answer as im not 100% sure.

 

[clement4413]

There is a mistake, I think, I never saw Sapphire HD4850 with GDDR5, that must be HD4870. HD 4850 exist with GDDR3 only except Gainward had come out HD4850 with GDDR5 but Ati haven't appreciated. Shame

So to answer your question, Yes you can crossfire with different GDDR types because, I saw we were able to make CF HD4870+4850 so you can CF HD4850 with different GDDR types but the HD4850 with GDDR5 will be bottlenecked by HD4850 with GDDR3

Could post the link about Hd 4850 GDDR5 ? I would like see that.
Please

 

[Haelis]

Here is the link to the card. It wasn't on newegg yesterday so it must have just appeared or became available again.

http://www.newegg.com/Product/Product.aspx?Item=N82E16814102901&cm_re=4850_512mb-_-14-102-901-_-Product

 

[clement4413]

THX for the links, I learnt something today ^^
I never heard about this card except Gainward but she doesn't exist anymore.

 

[brandenjaffri]

well sir i have the same graphics setup and am experiencing random crashes. i believe it is due to the difference in memory speeds;but i am still investigating; currently i am ugrading to a 1250 watt psu i believe the 12v consumption of my rig is 40a or so and my psu makes 50 but 80 plus certified so this may be the issue; ive had same problem for a few months i have replaced cpu;ram ; board; reinstalled os; so i have a bad card or not enough power; my crash dump says something about trying to resett the display driver but failed and says the file is atimpkg or something. im not an expert just a hobbiest. its getting real expensive though at least i got a sweet rig that crashes alot.!!!

am3 athlon II x4 635 @2.9
Rosewill RCX-ZAIO-92 92mm Sleeve CPU Cooler
ASUS Crosshair IV Formula AM3 AMD 890FX
Rosewill Libertas Series LIB-650 650W
G.SKILL Ripjaws Series 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 1333 x2 (16gb total system memory)
SAMSUNG Spinpoint F3 HD502HJ 500GB 7200 RPM
Microsoft Windows 7 Home Premium 64-bit

sapphire radeon 4850 512mb gddr3 625/993 (as listed in ccc overdrive function)
sapphire radeon 4850 512mb gddr5 625/750 (as listed in ccc overdrive function)

Antec Three Hundred Black Steel
Microsoft Comfort Curve Keyboard 2000
SAMSUNG BX2331 Glossy Black 23" Full HD LED Backlight LCD Monitor Slim Design
Rosewill RM-1600L Black 5 Buttons 1 x Wheel USB Laser Mouse